997915991761 has 8 divisors (see below), whose sum is σ = 1075425603840. Its totient is φ = 920513071632.

The previous prime is 997915991759. The next prime is 997915991773. The reversal of 997915991761 is 167199519799.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 997915991761 - 2¹ = 997915991759 is a prime.

It is a super-2 number, since 2×997915991761² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (997915991461) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26653555 + ... + 26690968.

It is an arithmetic number, because the mean of its divisors is an integer number (134428200480).

Almost surely, 2^997915991761 is an apocalyptic number.

It is an amenable number.

997915991761 is a deficient number, since it is larger than the sum of its proper divisors (77509612079).

997915991761 is a wasteful number, since it uses less digits than its factorization.

997915991761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53345975.

The product of its digits is 86802030, while the sum is 73.

The spelling of 997915991761 in words is "nine hundred ninety-seven billion, nine hundred fifteen million, nine hundred ninety-one thousand, seven hundred sixty-one".