997218575 has 6 divisors (see below), whose sum is σ = 1236551064. Its totient is φ = 797774840.

The previous prime is 997218557. The next prime is 997218581. The reversal of 997218575 is 575812799.

It is a happy number.

It is not a de Polignac number, because 997218575 - 2²⁶ = 930109711 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 19944347 + ... + 19944396.

It is an arithmetic number, because the mean of its divisors is an integer number (206091844).

Almost surely, 2^997218575 is an apocalyptic number.

997218575 is a deficient number, since it is larger than the sum of its proper divisors (239332489).

997218575 is a wasteful number, since it uses less digits than its factorization.

997218575 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39888753 (or 39888748 counting only the distinct ones).

The product of its digits is 1587600, while the sum is 53.

The square root of 997218575 is about 31578.7677878666. The cubic root of 997218575 is about 999.0719974109.

The spelling of 997218575 in words is "nine hundred ninety-seven million, two hundred eighteen thousand, five hundred seventy-five".