997787799 has 6 divisors (see below), whose sum is σ = 1441249056. Its totient is φ = 665191860.

The previous prime is 997787773. The next prime is 997787801.

997787799 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 997787799 - 2⁷ = 997787671 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (997787729) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 55432647 + ... + 55432664.

It is an arithmetic number, because the mean of its divisors is an integer number (240208176).

Almost surely, 2^997787799 is an apocalyptic number.

997787799 is a deficient number, since it is larger than the sum of its proper divisors (443461257).

997787799 is a wasteful number, since it uses less digits than its factorization.

997787799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110865317 (or 110865314 counting only the distinct ones).

The product of its digits is 126023688, while the sum is 72.

The square root of 997787799 is about 31587.7792666721. The cubic root of 997787799 is about 999.2620552381.

The spelling of 997787799 in words is "nine hundred ninety-seven million, seven hundred eighty-seven thousand, seven hundred ninety-nine".