21621411353477 has 16 divisors (see below), whose sum is σ = 23296719035520. Its totient is φ = 19947837988800.

The previous prime is 21621411353471. The next prime is 21621411353497. The reversal of 21621411353477 is 77435311412612.

It is a cyclic number.

It is not a de Polignac number, because 21621411353477 - 2²⁸ = 21621142918021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21621411353471) 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, 218988152 + ... + 219086862.

It is an arithmetic number, because the mean of its divisors is an integer number (1456044939720).

Almost surely, 2^{21621411353477} is an apocalyptic number.

It is an amenable number.

21621411353477 is a deficient number, since it is larger than the sum of its proper divisors (1675307682043).

21621411353477 is a wasteful number, since it uses less digits than its factorization.

21621411353477 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107324.

The product of its digits is 846720, while the sum is 47.

The spelling of 21621411353477 in words is "twenty-one trillion, six hundred twenty-one billion, four hundred eleven million, three hundred fifty-three thousand, four hundred seventy-seven".