21747572678 has 12 divisors (see below), whose sum is σ = 35323720668. Its totient is φ = 10037341080.

The previous prime is 21747572663. The next prime is 21747572681. The reversal of 21747572678 is 87627574712.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 32170628 + ... + 32171303.

It is an arithmetic number, because the mean of its divisors is an integer number (2943643389).

Almost surely, 2^21747572678 is an apocalyptic number.

21747572678 is a deficient number, since it is larger than the sum of its proper divisors (13576147990).

21747572678 is a wasteful number, since it uses less digits than its factorization.

21747572678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64341959 (or 64341946 counting only the distinct ones).

The product of its digits is 9219840, while the sum is 56.

The spelling of 21747572678 in words is "twenty-one billion, seven hundred forty-seven million, five hundred seventy-two thousand, six hundred seventy-eight".