21265994038 has 4 divisors (see below), whose sum is σ = 31898991060. Its totient is φ = 10632997018.

The previous prime is 21265994027. The next prime is 21265994039. The reversal of 21265994038 is 83049956212.

It is a semiprime because it is the product of two primes.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 21265993982 and 21265994000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21265994039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5316498508 + ... + 5316498511.

It is an arithmetic number, because the mean of its divisors is an integer number (7974747765).

Almost surely, 2^21265994038 is an apocalyptic number.

21265994038 is a deficient number, since it is larger than the sum of its proper divisors (10632997022).

21265994038 is a wasteful number, since it uses less digits than its factorization.

21265994038 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10632997021.

The product of its (nonzero) digits is 933120, while the sum is 49.

The spelling of 21265994038 in words is "twenty-one billion, two hundred sixty-five million, nine hundred ninety-four thousand, thirty-eight".