251340397 has 8 divisors (see below), whose sum is σ = 313359552. Its totient is φ = 195849600.

The previous prime is 251340391. The next prime is 251340407. The reversal of 251340397 is 793043152.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 251340397 - 2¹⁹ = 250816109 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251340391) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1632004 + ... + 1632157.

It is an arithmetic number, because the mean of its divisors is an integer number (39169944).

Almost surely, 2^251340397 is an apocalyptic number.

It is an amenable number.

251340397 is a deficient number, since it is larger than the sum of its proper divisors (62019155).

251340397 is a wasteful number, since it uses less digits than its factorization.

251340397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3264179.

The product of its (nonzero) digits is 22680, while the sum is 34.

The square root of 251340397 is about 15853.7187120246. The cubic root of 251340397 is about 631.0843817122.

The spelling of 251340397 in words is "two hundred fifty-one million, three hundred forty thousand, three hundred ninety-seven".