251428605 has 32 divisors (see below), whose sum is σ = 414142848. Its totient is φ = 130176000.

The previous prime is 251428603. The next prime is 251428607. The reversal of 251428605 is 506824152.

It is an interprime number because it is at equal distance from previous prime (251428603) and next prime (251428607).

It is not a de Polignac number, because 251428605 - 2¹ = 251428603 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251428601) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 138705 + ... + 140505.

It is an arithmetic number, because the mean of its divisors is an integer number (12941964).

Almost surely, 2^251428605 is an apocalyptic number.

It is an amenable number.

251428605 is a deficient number, since it is larger than the sum of its proper divisors (162714243).

251428605 is a wasteful number, since it uses less digits than its factorization.

251428605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2077.

The product of its (nonzero) digits is 19200, while the sum is 33.

The square root of 251428605 is about 15856.5004020433. The cubic root of 251428605 is about 631.1581995054.

The spelling of 251428605 in words is "two hundred fifty-one million, four hundred twenty-eight thousand, six hundred five".