997138850 has 12 divisors (see below), whose sum is σ = 1854678354. Its totient is φ = 398855520.

The previous prime is 997138847. The next prime is 997138903. The reversal of 997138850 is 58831799.

It can be written as a sum of positive squares in 3 ways, for example, as 825240529 + 171898321 = 28727^2 + 13111^2 .

It is a Harshad number since it is a multiple of its sum of digits (50), and also a Moran number because the ratio is a prime number: 19942777 = 997138850 / (9 + 9 + 7 + 1 + 3 + 8 + 8 + 5 + 0).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9971339 + ... + 9971438.

Almost surely, 2^997138850 is an apocalyptic number.

997138850 is a deficient number, since it is larger than the sum of its proper divisors (857539504).

997138850 is a wasteful number, since it uses less digits than its factorization.

997138850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19942789 (or 19942784 counting only the distinct ones).

The product of its (nonzero) digits is 544320, while the sum is 50.

The square root of 997138850 is about 31577.5054429573. The cubic root of 997138850 is about 999.0453723093.

The spelling of 997138850 in words is "nine hundred ninety-seven million, one hundred thirty-eight thousand, eight hundred fifty".