63506379489921 has 9 divisors (see below), whose sum is σ = 91731471573729. Its totient is φ = 42337570388436.

The previous prime is 63506379489919. The next prime is 63506379489923. The reversal of 63506379489921 is 12998497360536.

The square root of 63506379489921 is 7969089.

It is a perfect power (a square), and thus also a powerful number.

63506379489921 is a `hidden beast` number, since 6 + 3 + 50 + 6 + 3 + 7 + 9 + 489 + 92 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (63506379489919) and next prime (63506379489923).

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 63506379489921 - 2¹ = 63506379489919 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 63506379489921.

It is not an unprimeable number, because it can be changed into a prime (63506379489923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 22579086 + ... + 25235448.

It is a 1-persistent number, because it is pandigital, but 2⋅63506379489921 = 127012758979842 is not.

Almost surely, 2^{63506379489921} is an apocalyptic number.

63506379489921 is the 7969089-th square number.

63506379489921 is the 3984545-th centered octagonal number.

It is an amenable number.

63506379489921 is a deficient number, since it is larger than the sum of its proper divisors (28225092083808).

63506379489921 is an frugal number, since it uses more digits than its factorization.

63506379489921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5312732 (or 2656366 counting only the distinct ones).

The product of its (nonzero) digits is 529079040, while the sum is 72.

The spelling of 63506379489921 in words is "sixty-three trillion, five hundred six billion, three hundred seventy-nine million, four hundred eighty-nine thousand, nine hundred twenty-one".