90712981 has 2 divisors, whose sum is σ = 90712982. Its totient is φ = 90712980.

The previous prime is 90712949. The next prime is 90712991. The reversal of 90712981 is 18921709.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71132356 + 19580625 = 8434^2 + 4425^2 .

It is a cyclic number.

It is not a de Polignac number, because 90712981 - 2⁵ = 90712949 is a prime.

It is a super-2 number, since 2×90712981² = 16457689843812722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 90712981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90712991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45356490 + 45356491.

It is an arithmetic number, because the mean of its divisors is an integer number (45356491).

Almost surely, 2^90712981 is an apocalyptic number.

It is an amenable number.

90712981 is a deficient number, since it is larger than the sum of its proper divisors (1).

90712981 is an equidigital number, since it uses as much as digits as its factorization.

90712981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9072, while the sum is 37.

The square root of 90712981 is about 9524.3362498391. The cubic root of 90712981 is about 449.3207546637.

The spelling of 90712981 in words is "ninety million, seven hundred twelve thousand, nine hundred eighty-one".