21385634562 has 24 divisors (see below), whose sum is σ = 46389642156. Its totient is φ = 7120221696.

The previous prime is 21385634519. The next prime is 21385634573. The reversal of 21385634562 is 26543658312.

21385634562 is a `hidden beast` number, since 2 + 1 + 3 + 8 + 5 + 634 + 5 + 6 + 2 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 16806270321 + 4579364241 = 129639^2 + 67671^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 677743 + ... + 708594.

Almost surely, 2^21385634562 is an apocalyptic number.

21385634562 is an abundant number, since it is smaller than the sum of its proper divisors (25004007594).

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

21385634562 is a wasteful number, since it uses less digits than its factorization.

21385634562 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1387202 (or 1387199 counting only the distinct ones).

The product of its digits is 1036800, while the sum is 45.

The spelling of 21385634562 in words is "twenty-one billion, three hundred eighty-five million, six hundred thirty-four thousand, five hundred sixty-two".