21873639892 has 48 divisors (see below), whose sum is σ = 42647374224. Its totient is φ = 9751680000.

The previous prime is 21873639707. The next prime is 21873639899. The reversal of 21873639892 is 29893637812.

It can be written as a sum of positive squares in 8 ways, for example, as 966215056 + 20907424836 = 31084^2 + 144594^2 .

It is a super-2 number, since 2×21873639892² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21873639899) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 164542 + ... + 266122.

It is an arithmetic number, because the mean of its divisors is an integer number (888486963).

Almost surely, 2^21873639892 is an apocalyptic number.

It is an amenable number.

21873639892 is a deficient number, since it is larger than the sum of its proper divisors (20773734332).

21873639892 is a wasteful number, since it uses less digits than its factorization.

21873639892 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101740 (or 101738 counting only the distinct ones).

The product of its digits is 7838208, while the sum is 58.

The spelling of 21873639892 in words is "twenty-one billion, eight hundred seventy-three million, six hundred thirty-nine thousand, eight hundred ninety-two".