628401278 has 4 divisors (see below), whose sum is σ = 942601920. Its totient is φ = 314200638.

The previous prime is 628401247. The next prime is 628401283. The reversal of 628401278 is 872104826.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 157100318 + ... + 157100321.

It is an arithmetic number, because the mean of its divisors is an integer number (235650480).

Almost surely, 2^628401278 is an apocalyptic number.

628401278 is a deficient number, since it is larger than the sum of its proper divisors (314200642).

628401278 is a wasteful number, since it uses less digits than its factorization.

628401278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 314200641.

The product of its (nonzero) digits is 43008, while the sum is 38.

The square root of 628401278 is about 25067.9332614398. The cubic root of 628401278 is about 856.5361292989.

The spelling of 628401278 in words is "six hundred twenty-eight million, four hundred one thousand, two hundred seventy-eight".