21739395357 has 40 divisors (see below), whose sum is σ = 34665744960. Its totient is φ = 13536694080.

The previous prime is 21739395347. The next prime is 21739395383. The reversal of 21739395357 is 75359393712.

21739395357 is a `hidden beast` number, since 2 + 1 + 73 + 9 + 39 + 535 + 7 = 666.

It is not a de Polignac number, because 21739395357 - 2¹⁹ = 21738871069 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21739395347) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 9793 + ... + 208745.

It is an arithmetic number, because the mean of its divisors is an integer number (866643624).

Almost surely, 2^21739395357 is an apocalyptic number.

21739395357 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

21739395357 is a deficient number, since it is larger than the sum of its proper divisors (12926349603).

21739395357 is a wasteful number, since it uses less digits than its factorization.

21739395357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199055 (or 199046 counting only the distinct ones).

The product of its digits is 5358150, while the sum is 54.

The spelling of 21739395357 in words is "twenty-one billion, seven hundred thirty-nine million, three hundred ninety-five thousand, three hundred fifty-seven".