997181799 has 4 divisors (see below), whose sum is σ = 1329575736. Its totient is φ = 664787864.

The previous prime is 997181797. The next prime is 997181839.

997181799 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 997181799 - 2¹ = 997181797 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (997181797) 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, 166196964 + ... + 166196969.

It is an arithmetic number, because the mean of its divisors is an integer number (332393934).

Almost surely, 2^997181799 is an apocalyptic number.

997181799 is a deficient number, since it is larger than the sum of its proper divisors (332393937).

997181799 is a wasteful number, since it uses less digits than its factorization.

997181799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332393936.

The product of its digits is 2571912, while the sum is 60.

The square root of 997181799 is about 31578.1854925200. The cubic root of 997181799 is about 999.0597158094.

The spelling of 997181799 in words is "nine hundred ninety-seven million, one hundred eighty-one thousand, seven hundred ninety-nine".