1663120628501 has 4 divisors (see below), whose sum is σ = 1663137379404. Its totient is φ = 1663103877600.

The previous prime is 1663120628473. The next prime is 1663120628509. The reversal of 1663120628501 is 1058260213661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1492675506001 + 170445122500 = 1221751^2 + 412850^2 .

It is a cyclic number.

It is not a de Polignac number, because 1663120628501 - 2¹⁴ = 1663120612117 is a prime.

It is a super-2 number, since 2×1663120628501² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1663120628509) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8225630 + ... + 8425391.

It is an arithmetic number, because the mean of its divisors is an integer number (415784344851).

Almost surely, 2^{1663120628501} is an apocalyptic number.

It is an amenable number.

1663120628501 is a deficient number, since it is larger than the sum of its proper divisors (16750903).

1663120628501 is an equidigital number, since it uses as much as digits as its factorization.

1663120628501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16750902.

The product of its (nonzero) digits is 103680, while the sum is 41.

The spelling of 1663120628501 in words is "one trillion, six hundred sixty-three billion, one hundred twenty million, six hundred twenty-eight thousand, five hundred one".