21247564930 has 32 divisors (see below), whose sum is σ = 38824768368. Its totient is φ = 8371200000.

The previous prime is 21247564927. The next prime is 21247564939. The reversal of 21247564930 is 3946574212.

It can be written as a sum of positive squares in 8 ways, for example, as 11504493081 + 9743071849 = 107259^2 + 98707^2 .

It is not an unprimeable number, because it can be changed into a prime (21247564939) 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, 140430 + ... + 249430.

Almost surely, 2^21247564930 is an apocalyptic number.

21247564930 is a deficient number, since it is larger than the sum of its proper divisors (17577203438).

21247564930 is a wasteful number, since it uses less digits than its factorization.

21247564930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109302.

The product of its (nonzero) digits is 362880, while the sum is 43.

The spelling of 21247564930 in words is "twenty-one billion, two hundred forty-seven million, five hundred sixty-four thousand, nine hundred thirty".