642657250 has 32 divisors (see below), whose sum is σ = 1205184240. Its totient is φ = 256608000.

The previous prime is 642657229. The next prime is 642657251. The reversal of 642657250 is 52756246.

642657250 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 123409881 + 519247369 = 11109^2 + 22787^2 .

It is not an unprimeable number, because it can be changed into a prime (642657251) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 163306 + ... + 167194.

Almost surely, 2^642657250 is an apocalyptic number.

642657250 is a deficient number, since it is larger than the sum of its proper divisors (562526990).

642657250 is a wasteful number, since it uses less digits than its factorization.

642657250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4567 (or 4557 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 37.

The square root of 642657250 is about 25350.6853950736. The cubic root of 642657250 is about 862.9649107362.

The spelling of 642657250 in words is "six hundred forty-two million, six hundred fifty-seven thousand, two hundred fifty".