21357833511 has 32 divisors (see below), whose sum is σ = 33977991168. Its totient is φ = 11667759840.

The previous prime is 21357833503. The next prime is 21357833531. The reversal of 21357833511 is 11533875312.

It is not a de Polignac number, because 21357833511 - 2³ = 21357833503 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21357833511.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21357833531) 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, 1009140 + ... + 1030086.

It is an arithmetic number, because the mean of its divisors is an integer number (1061812224).

Almost surely, 2^21357833511 is an apocalyptic number.

21357833511 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21357833511 is a deficient number, since it is larger than the sum of its proper divisors (12620157657).

21357833511 is a wasteful number, since it uses less digits than its factorization.

21357833511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23091.

The product of its digits is 75600, while the sum is 39.

The spelling of 21357833511 in words is "twenty-one billion, three hundred fifty-seven million, eight hundred thirty-three thousand, five hundred eleven".