21730697604 has 192 divisors, whose sum is σ = 70553548800. Its totient is φ = 5619196800.

The previous prime is 21730697567. The next prime is 21730697633. The reversal of 21730697604 is 40679603712.

21730697604 is a `hidden beast` number, since 2 + 1 + 7 + 30 + 6 + 9 + 7 + 604 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 21730697604.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1898659 + ... + 1910069.

It is an arithmetic number, because the mean of its divisors is an integer number (367466400).

Almost surely, 2^21730697604 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21730697604, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35276774400).

21730697604 is an abundant number, since it is smaller than the sum of its proper divisors (48822851196).

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

21730697604 is a wasteful number, since it uses less digits than its factorization.

21730697604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11671 (or 11663 counting only the distinct ones).

The product of its (nonzero) digits is 381024, while the sum is 45.

The spelling of 21730697604 in words is "twenty-one billion, seven hundred thirty million, six hundred ninety-seven thousand, six hundred four".