90631897 has 2 divisors, whose sum is σ = 90631898. Its totient is φ = 90631896.

The previous prime is 90631867. The next prime is 90631903. The reversal of 90631897 is 79813609.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 76108176 + 14523721 = 8724^2 + 3811^2 .

It is an emirp because it is prime and its reverse (79813609) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90631897 - 2¹⁹ = 90107609 is a prime.

It is a super-3 number, since 3×90631897³ (a number of 25 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (90631867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45315948 + 45315949.

It is an arithmetic number, because the mean of its divisors is an integer number (45315949).

Almost surely, 2^90631897 is an apocalyptic number.

It is an amenable number.

90631897 is a deficient number, since it is larger than the sum of its proper divisors (1).

90631897 is an equidigital number, since it uses as much as digits as its factorization.

90631897 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 81648, while the sum is 43.

The square root of 90631897 is about 9520.0786236249. The cubic root of 90631897 is about 449.1868393033.

The spelling of 90631897 in words is "ninety million, six hundred thirty-one thousand, eight hundred ninety-seven".