21951341788 has 24 divisors (see below), whose sum is σ = 38976233184. Its totient is φ = 10815436800.

The previous prime is 21951341777. The next prime is 21951341791. The reversal of 21951341788 is 88714315912.

It is a super-2 number, since 2×21951341788² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 553668 + ... + 591988.

It is an arithmetic number, because the mean of its divisors is an integer number (1624009716).

Almost surely, 2^21951341788 is an apocalyptic number.

It is an amenable number.

21951341788 is a deficient number, since it is larger than the sum of its proper divisors (17024891396).

21951341788 is a wasteful number, since it uses less digits than its factorization.

21951341788 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40413 (or 40411 counting only the distinct ones).

The product of its digits is 483840, while the sum is 49.

The spelling of 21951341788 in words is "twenty-one billion, nine hundred fifty-one million, three hundred forty-one thousand, seven hundred eighty-eight".