642647210 has 8 divisors (see below), whose sum is σ = 1156764996. Its totient is φ = 257058880.

The previous prime is 642647147. The next prime is 642647219. The reversal of 642647210 is 12746246.

It can be written as a sum of positive squares in 2 ways, for example, as 641456929 + 1190281 = 25327^2 + 1091^2 .

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (642647219) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32132351 + ... + 32132370.

Almost surely, 2^642647210 is an apocalyptic number.

642647210 is a deficient number, since it is larger than the sum of its proper divisors (514117786).

642647210 is a wasteful number, since it uses less digits than its factorization.

642647210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64264728.

The product of its (nonzero) digits is 16128, while the sum is 32.

The square root of 642647210 is about 25350.4873720408. The cubic root of 642647210 is about 862.9604167841.

The spelling of 642647210 in words is "six hundred forty-two million, six hundred forty-seven thousand, two hundred ten".