251401389 has 12 divisors (see below), whose sum is σ = 356080704. Its totient is φ = 157741504.

The previous prime is 251401361. The next prime is 251401391. The reversal of 251401389 is 983104152.

It is not a de Polignac number, because 251401389 - 2⁵ = 251401357 is a prime.

It is a super-2 number, since 2×251401389² = 126405316782258642, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251401309) 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, 144117 + ... + 145850.

It is an arithmetic number, because the mean of its divisors is an integer number (29673392).

Almost surely, 2^251401389 is an apocalyptic number.

It is an amenable number.

251401389 is a deficient number, since it is larger than the sum of its proper divisors (104679315).

251401389 is a wasteful number, since it uses less digits than its factorization.

251401389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 290004 (or 289987 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 251401389 is about 15855.6421818859. The cubic root of 251401389 is about 631.1354253513.

The spelling of 251401389 in words is "two hundred fifty-one million, four hundred one thousand, three hundred eighty-nine".