21355462535621 has 16 divisors (see below), whose sum is σ = 22105927080960. Its totient is φ = 20605938312960.

The previous prime is 21355462535569. The next prime is 21355462535623. The reversal of 21355462535621 is 12653526455312.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21355462535621 is a prime.

It is a super-2 number, since 2×21355462535621² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21355462535621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21355462535623) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 881607116 + ... + 881631338.

It is an arithmetic number, because the mean of its divisors is an integer number (1381620442560).

Almost surely, 2^{21355462535621} is an apocalyptic number.

It is an amenable number.

21355462535621 is a deficient number, since it is larger than the sum of its proper divisors (750464545339).

21355462535621 is a wasteful number, since it uses less digits than its factorization.

21355462535621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42356.

The product of its digits is 6480000, while the sum is 50.

The spelling of 21355462535621 in words is "twenty-one trillion, three hundred fifty-five billion, four hundred sixty-two million, five hundred thirty-five thousand, six hundred twenty-one".