21935531 has 2 divisors, whose sum is σ = 21935532. Its totient is φ = 21935530.

The previous prime is 21935527. The next prime is 21935549. The reversal of 21935531 is 13553912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21935531 - 2² = 21935527 is a prime.

It is a super-2 number, since 2×21935531² = 962335040503922, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21935494 and 21935503.

It is not a weakly prime, because it can be changed into another prime (21935581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10967765 + 10967766.

It is an arithmetic number, because the mean of its divisors is an integer number (10967766).

Almost surely, 2^21935531 is an apocalyptic number.

21935531 is a deficient number, since it is larger than the sum of its proper divisors (1).

21935531 is an equidigital number, since it uses as much as digits as its factorization.

21935531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4050, while the sum is 29.

The square root of 21935531 is about 4683.5382991922. The cubic root of 21935531 is about 279.9299612236.

The spelling of 21935531 in words is "twenty-one million, nine hundred thirty-five thousand, five hundred thirty-one".