251162666 has 4 divisors (see below), whose sum is σ = 376744002. Its totient is φ = 125581332.

The previous prime is 251162657. The next prime is 251162683. The reversal of 251162666 is 666261152.

251162666 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 178997641 + 72165025 = 13379^2 + 8495^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62790665 + ... + 62790668.

Almost surely, 2^251162666 is an apocalyptic number.

251162666 is a deficient number, since it is larger than the sum of its proper divisors (125581336).

251162666 is a wasteful number, since it uses less digits than its factorization.

251162666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125581335.

The product of its digits is 25920, while the sum is 35.

The square root of 251162666 is about 15848.1123797126. The cubic root of 251162666 is about 630.9355931794.

It can be divided in two parts, 251 and 162666, that multiplied together give a triangular number (40829166 = T₉₀₃₆).

The spelling of 251162666 in words is "two hundred fifty-one million, one hundred sixty-two thousand, six hundred sixty-six".