21779025917140 has 12 divisors (see below), whose sum is σ = 45735954426036. Its totient is φ = 8711610366848.

The previous prime is 21779025917119. The next prime is 21779025917141. The reversal of 21779025917140 is 4171952097712.

It can be written as a sum of positive squares in 2 ways, for example, as 7395984837136 + 14383041080004 = 2719556^2 + 3792498^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21779025917141) 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, 544475647909 + ... + 544475647948.

It is an arithmetic number, because the mean of its divisors is an integer number (3811329535503).

Almost surely, 2^{21779025917140} is an apocalyptic number.

21779025917140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21779025917140 is an abundant number, since it is smaller than the sum of its proper divisors (23956928508896).

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

21779025917140 is a wasteful number, since it uses less digits than its factorization.

21779025917140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1088951295866 (or 1088951295864 counting only the distinct ones).

The product of its (nonzero) digits is 2222640, while the sum is 55.

The spelling of 21779025917140 in words is "twenty-one trillion, seven hundred seventy-nine billion, twenty-five million, nine hundred seventeen thousand, one hundred forty".