21563370774 has 40 divisors (see below), whose sum is σ = 52710466248. Its totient is φ = 6534354240.

The previous prime is 21563370721. The next prime is 21563370791. The reversal of 21563370774 is 47707336512.

21563370774 is a `hidden beast` number, since 2 + 1 + 5 + 633 + 7 + 0 + 7 + 7 + 4 = 666.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 6048547 + ... + 6052110.

Almost surely, 2^21563370774 is an apocalyptic number.

21563370774 is an abundant number, since it is smaller than the sum of its proper divisors (31147095474).

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

21563370774 is a wasteful number, since it uses less digits than its factorization.

21563370774 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12100682 (or 12100673 counting only the distinct ones).

The product of its (nonzero) digits is 740880, while the sum is 45.

The spelling of 21563370774 in words is "twenty-one billion, five hundred sixty-three million, three hundred seventy thousand, seven hundred seventy-four".