1387135251 has 12 divisors (see below), whose sum is σ = 2004130128. Its totient is φ = 924530544.

The previous prime is 1387135231. The next prime is 1387135297. The reversal of 1387135251 is 1525317831.

It is a happy number.

It is not a de Polignac number, because 1387135251 - 2⁶ = 1387135187 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (1387135231) 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, 25441 + ... + 58493.

It is an arithmetic number, because the mean of its divisors is an integer number (167010844).

Almost surely, 2^1387135251 is an apocalyptic number.

1387135251 is a deficient number, since it is larger than the sum of its proper divisors (616994877).

1387135251 is a wasteful number, since it uses less digits than its factorization.

1387135251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37722 (or 37719 counting only the distinct ones).

The product of its digits is 25200, while the sum is 36.

The square root of 1387135251 is about 37244.2646725640. The cubic root of 1387135251 is about 1115.2518085050.

The spelling of 1387135251 in words is "one billion, three hundred eighty-seven million, one hundred thirty-five thousand, two hundred fifty-one".