997519881 has 4 divisors (see below), whose sum is σ = 1330026512. Its totient is φ = 665013252.

The previous prime is 997519843. The next prime is 997519883. The reversal of 997519881 is 188915799.

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 not a de Polignac number, because 997519881 - 2¹⁰ = 997518857 is a prime.

It is a super-2 number, since 2×997519881² = 1990091825980508322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (997519883) 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, 166253311 + ... + 166253316.

It is an arithmetic number, because the mean of its divisors is an integer number (332506628).

Almost surely, 2^997519881 is an apocalyptic number.

It is an amenable number.

997519881 is a deficient number, since it is larger than the sum of its proper divisors (332506631).

997519881 is a wasteful number, since it uses less digits than its factorization.

997519881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332506630.

The product of its digits is 1632960, while the sum is 57.

The square root of 997519881 is about 31583.5381330211. The cubic root of 997519881 is about 999.1726092801.

The spelling of 997519881 in words is "nine hundred ninety-seven million, five hundred nineteen thousand, eight hundred eighty-one".