21086963 has 2 divisors, whose sum is σ = 21086964. Its totient is φ = 21086962.

The previous prime is 21086957. The next prime is 21086971. The reversal of 21086963 is 36968012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21086963 - 2¹⁴ = 21070579 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21086563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10543481 + 10543482.

It is an arithmetic number, because the mean of its divisors is an integer number (10543482).

Almost surely, 2^21086963 is an apocalyptic number.

21086963 is a deficient number, since it is larger than the sum of its proper divisors (1).

21086963 is an equidigital number, since it uses as much as digits as its factorization.

21086963 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 35.

The square root of 21086963 is about 4592.0543333023. The cubic root of 21086963 is about 276.2727254156.

The spelling of 21086963 in words is "twenty-one million, eighty-six thousand, nine hundred sixty-three".