2138081787 has 12 divisors (see below), whose sum is σ = 3091180144. Its totient is φ = 1424077200.

The previous prime is 2138081783. The next prime is 2138081831. The reversal of 2138081787 is 7871808312.

It is not a de Polignac number, because 2138081787 - 2² = 2138081783 is a prime.

It is a super-3 number, since 3×2138081787³ (a number of 29 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2138081783) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 98839 + ... + 118512.

Almost surely, 2^2138081787 is an apocalyptic number.

2138081787 is a deficient number, since it is larger than the sum of its proper divisors (953098357).

2138081787 is a wasteful number, since it uses less digits than its factorization.

2138081787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 218450 (or 218447 counting only the distinct ones).

The product of its (nonzero) digits is 150528, while the sum is 45.

The square root of 2138081787 is about 46239.3964817881. The cubic root of 2138081787 is about 1288.2735928694.

The spelling of 2138081787 in words is "two billion, one hundred thirty-eight million, eighty-one thousand, seven hundred eighty-seven".