97631809 has 4 divisors (see below), whose sum is σ = 106507440. Its totient is φ = 88756180.

The previous prime is 97631773. The next prime is 97631813. The reversal of 97631809 is 90813679.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-97631809 is a prime.

It is a super-2 number, since 2×97631809² = 19063940257224962, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (97631869) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4437799 + ... + 4437820.

It is an arithmetic number, because the mean of its divisors is an integer number (26626860).

Almost surely, 2^97631809 is an apocalyptic number.

It is an amenable number.

97631809 is a deficient number, since it is larger than the sum of its proper divisors (8875631).

97631809 is a wasteful number, since it uses less digits than its factorization.

97631809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8875630.

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

The square root of 97631809 is about 9880.8809829893. The cubic root of 97631809 is about 460.4655164547.

The spelling of 97631809 in words is "ninety-seven million, six hundred thirty-one thousand, eight hundred nine".