2138991606 has 24 divisors (see below), whose sum is σ = 4642399944. Its totient is φ = 711779040.

The previous prime is 2138991587. The next prime is 2138991637. The reversal of 2138991606 is 6061998312.

It is a happy number.

2138991606 is a `hidden beast` number, since 2 + 1 + 38 + 9 + 9 + 1 + 606 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 90655 + ... + 111786.

It is an arithmetic number, because the mean of its divisors is an integer number (193433331).

Almost surely, 2^2138991606 is an apocalyptic number.

2138991606 is an abundant number, since it is smaller than the sum of its proper divisors (2503408338).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2138991606 is a wasteful number, since it uses less digits than its factorization.

2138991606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203036 (or 203033 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The square root of 2138991606 is about 46249.2335720280. The cubic root of 2138991606 is about 1288.4563001890.

The spelling of 2138991606 in words is "two billion, one hundred thirty-eight million, nine hundred ninety-one thousand, six hundred six".