90211631 has 2 divisors, whose sum is σ = 90211632. Its totient is φ = 90211630.

The previous prime is 90211613. The next prime is 90211637. The reversal of 90211631 is 13611209.

It is a happy number.

Together with previous prime (90211613) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is an emirp because it is prime and its reverse (13611209) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90211631 - 2⁶ = 90211567 is a prime.

It is a super-2 number, since 2×90211631² = 16276276735360322, 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 = 90211597 and 90211606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90211637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45105815 + 45105816.

It is an arithmetic number, because the mean of its divisors is an integer number (45105816).

Almost surely, 2^90211631 is an apocalyptic number.

90211631 is a deficient number, since it is larger than the sum of its proper divisors (1).

90211631 is an equidigital number, since it uses as much as digits as its factorization.

90211631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 23.

The square root of 90211631 is about 9497.9803642669. The cubic root of 90211631 is about 448.4914604930.

The spelling of 90211631 in words is "ninety million, two hundred eleven thousand, six hundred thirty-one".