1387256251 has 2 divisors, whose sum is σ = 1387256252. Its totient is φ = 1387256250.

The previous prime is 1387256173. The next prime is 1387256309. The reversal of 1387256251 is 1526527831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1387256251 - 2⁹ = 1387255739 is a prime.

It is not a weakly prime, because it can be changed into another prime (1387256551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 693628125 + 693628126.

It is an arithmetic number, because the mean of its divisors is an integer number (693628126).

Almost surely, 2^1387256251 is an apocalyptic number.

1387256251 is a deficient number, since it is larger than the sum of its proper divisors (1).

1387256251 is an equidigital number, since it uses as much as digits as its factorization.

1387256251 is an evil number, because the sum of its binary digits is even.

The product of its digits is 100800, while the sum is 40.

The square root of 1387256251 is about 37245.8890483232. The cubic root of 1387256251 is about 1115.2842354187.

The spelling of 1387256251 in words is "one billion, three hundred eighty-seven million, two hundred fifty-six thousand, two hundred fifty-one".