21043542396 has 24 divisors (see below), whose sum is σ = 49110054784. Its totient is φ = 7013306160.

The previous prime is 21043542389. The next prime is 21043542413. The reversal of 21043542396 is 69324534012.

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, 76960 + ... + 219111.

Almost surely, 2^21043542396 is an apocalyptic number.

It is an amenable number.

21043542396 is an abundant number, since it is smaller than the sum of its proper divisors (28066512388).

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

21043542396 is a wasteful number, since it uses less digits than its factorization.

21043542396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 302001 (or 301999 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 39.

The spelling of 21043542396 in words is "twenty-one billion, forty-three million, five hundred forty-two thousand, three hundred ninety-six".