21371641361640 has 96 divisors (see below), whose sum is σ = 73113509944800. Its totient is φ = 5399151500160.

The previous prime is 21371641361639. The next prime is 21371641361657. The reversal of 21371641361640 is 4616314617312.

21371641361640 is a `hidden beast` number, since 2 + 1 + 3 + 7 + 16 + 4 + 13 + 616 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1562247646 + ... + 1562261325.

It is an arithmetic number, because the mean of its divisors is an integer number (761599061925).

Almost surely, 2^{21371641361640} is an apocalyptic number.

21371641361640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21371641361640 is an abundant number, since it is smaller than the sum of its proper divisors (51741868583160).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21371641361640 is a wasteful number, since it uses less digits than its factorization.

21371641361640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3124509007 (or 3124509000 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

Adding to 21371641361640 its reverse (4616314617312), we get a palindrome (25987955978952).

The spelling of 21371641361640 in words is "twenty-one trillion, three hundred seventy-one billion, six hundred forty-one million, three hundred sixty-one thousand, six hundred forty".