21767874064 has 20 divisors (see below), whose sum is σ = 42325354620. Its totient is φ = 10845201920.

The previous prime is 21767874053. The next prime is 21767874067. The reversal of 21767874064 is 46047876712.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 6538339600 + 15229534464 = 80860^2 + 123408^2 .

It is not an unprimeable number, because it can be changed into a prime (21767874067) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2416309 + ... + 2425300.

It is an arithmetic number, because the mean of its divisors is an integer number (2116267731).

Almost surely, 2^21767874064 is an apocalyptic number.

It is an amenable number.

21767874064 is a deficient number, since it is larger than the sum of its proper divisors (20557480556).

21767874064 is a wasteful number, since it uses less digits than its factorization.

21767874064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4841898 (or 4841892 counting only the distinct ones).

The product of its (nonzero) digits is 3161088, while the sum is 52.

The spelling of 21767874064 in words is "twenty-one billion, seven hundred sixty-seven million, eight hundred seventy-four thousand, sixty-four".