21065352231 has 64 divisors (see below), whose sum is σ = 36995973120. Its totient is φ = 10329068160.

The previous prime is 21065352199. The next prime is 21065352277. The reversal of 21065352231 is 13225356012.

It is not a de Polignac number, because 21065352231 - 2⁵ = 21065352199 is a prime.

It is a super-2 number, since 2×21065352231² (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 (21065350231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1207090 + ... + 1224416.

It is an arithmetic number, because the mean of its divisors is an integer number (578062080).

Almost surely, 2^21065352231 is an apocalyptic number.

21065352231 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21065352231 is a deficient number, since it is larger than the sum of its proper divisors (15930620889).

21065352231 is a wasteful number, since it uses less digits than its factorization.

21065352231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17644.

The product of its (nonzero) digits is 10800, while the sum is 30.

The spelling of 21065352231 in words is "twenty-one billion, sixty-five million, three hundred fifty-two thousand, two hundred thirty-one".