21137827693 has 32 divisors (see below), whose sum is σ = 24474804480. Its totient is φ = 18127872000.

The previous prime is 21137827663. The next prime is 21137827699. The reversal of 21137827693 is 39672873112.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21137827693 is a prime.

It is a super-3 number, since 3×21137827693³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21137827699) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 929013 + ... + 951493.

It is an arithmetic number, because the mean of its divisors is an integer number (764837640).

Almost surely, 2^21137827693 is an apocalyptic number.

It is an amenable number.

21137827693 is a deficient number, since it is larger than the sum of its proper divisors (3336976787).

21137827693 is a wasteful number, since it uses less digits than its factorization.

21137827693 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22629.

The product of its digits is 762048, while the sum is 49.

The spelling of 21137827693 in words is "twenty-one billion, one hundred thirty-seven million, eight hundred twenty-seven thousand, six hundred ninety-three".