21772799985 has 16 divisors (see below), whose sum is σ = 34838772480. Its totient is φ = 11611395840.

The previous prime is 21772799981. The next prime is 21772799989. The reversal of 21772799985 is 58999727712.

It is an interprime number because it is at equal distance from previous prime (21772799981) and next prime (21772799989).

It is not a de Polignac number, because 21772799985 - 2² = 21772799981 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21772799981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 246105 + ... + 322665.

It is an arithmetic number, because the mean of its divisors is an integer number (2177423280).

Almost surely, 2^21772799985 is an apocalyptic number.

It is an amenable number.

21772799985 is a deficient number, since it is larger than the sum of its proper divisors (13065972495).

21772799985 is a wasteful number, since it uses less digits than its factorization.

21772799985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95528.

The product of its digits is 40007520, while the sum is 66.

The spelling of 21772799985 in words is "twenty-one billion, seven hundred seventy-two million, seven hundred ninety-nine thousand, nine hundred eighty-five".