21097194534 has 48 divisors (see below), whose sum is σ = 49614469632. Its totient is φ = 6440321664.

The previous prime is 21097194509. The next prime is 21097194551. The reversal of 21097194534 is 43549179012.

21097194534 is a `hidden beast` number, since 2 + 10 + 97 + 19 + 4 + 534 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 21097194534.

It is a congruent number.

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, 325239 + ... + 384674.

It is an arithmetic number, because the mean of its divisors is an integer number (1033634784).

Almost surely, 2^21097194534 is an apocalyptic number.

21097194534 is an abundant number, since it is smaller than the sum of its proper divisors (28517275098).

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

21097194534 is a wasteful number, since it uses less digits than its factorization.

21097194534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 710061 (or 710058 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The spelling of 21097194534 in words is "twenty-one billion, ninety-seven million, one hundred ninety-four thousand, five hundred thirty-four".