251409601 has 4 divisors (see below), whose sum is σ = 252218304. Its totient is φ = 250600900.

The previous prime is 251409589. The next prime is 251409629. The reversal of 251409601 is 106904152.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 251409601 - 2⁵ = 251409569 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 251409601.

It is not an unprimeable number, because it can be changed into a prime (251409001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 403885 + ... + 404506.

It is an arithmetic number, because the mean of its divisors is an integer number (63054576).

Almost surely, 2^251409601 is an apocalyptic number.

It is an amenable number.

251409601 is a deficient number, since it is larger than the sum of its proper divisors (808703).

251409601 is an equidigital number, since it uses as much as digits as its factorization.

251409601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 808702.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 251409601 is about 15855.9011412155. The cubic root of 251409601 is about 631.1422972673.

The spelling of 251409601 in words is "two hundred fifty-one million, four hundred nine thousand, six hundred one".