628781715 has 24 divisors (see below), whose sum is σ = 1094052960. Its totient is φ = 334068864.

The previous prime is 628781641. The next prime is 628781719. The reversal of 628781715 is 517187826.

It is a happy number.

628781715 is a `hidden beast` number, since 628 + 7 + 8 + 1 + 7 + 15 = 666.

It is not a de Polignac number, because 628781715 - 2¹⁵ = 628748947 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (628781719) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14730 + ... + 38399.

It is an arithmetic number, because the mean of its divisors is an integer number (45585540).

Almost surely, 2^628781715 is an apocalyptic number.

628781715 is a deficient number, since it is larger than the sum of its proper divisors (465271245).

628781715 is a wasteful number, since it uses less digits than its factorization.

628781715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53403 (or 53400 counting only the distinct ones).

The product of its digits is 188160, while the sum is 45.

The square root of 628781715 is about 25075.5202338855. The cubic root of 628781715 is about 856.7089447223.

The spelling of 628781715 in words is "six hundred twenty-eight million, seven hundred eighty-one thousand, seven hundred fifteen".