997638910 has 16 divisors (see below), whose sum is σ = 1796134176. Its totient is φ = 398970208.

The previous prime is 997638899. The next prime is 997638949. The reversal of 997638910 is 19836799.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 61959 + ... + 76381.

It is an arithmetic number, because the mean of its divisors is an integer number (112258386).

Almost surely, 2^997638910 is an apocalyptic number.

997638910 is a deficient number, since it is larger than the sum of its proper divisors (798495266).

997638910 is a wasteful number, since it uses less digits than its factorization.

997638910 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21347.

The product of its (nonzero) digits is 734832, while the sum is 52.

The square root of 997638910 is about 31585.4224287091. The cubic root of 997638910 is about 999.2123497700.

The spelling of 997638910 in words is "nine hundred ninety-seven million, six hundred thirty-eight thousand, nine hundred ten".