642745234 has 4 divisors (see below), whose sum is σ = 964117854. Its totient is φ = 321372616.

The previous prime is 642745223. The next prime is 642745247. The reversal of 642745234 is 432547246.

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., 407030625 + 235714609 = 20175^2 + 15353^2 .

It is a junction number, because it is equal to n+sod(n) for n = 642745193 and 642745202.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160686307 + ... + 160686310.

Almost surely, 2^642745234 is an apocalyptic number.

642745234 is a deficient number, since it is larger than the sum of its proper divisors (321372620).

642745234 is a wasteful number, since it uses less digits than its factorization.

642745234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321372619.

The product of its digits is 161280, while the sum is 37.

The square root of 642745234 is about 25352.4206733795. The cubic root of 642745234 is about 863.0042907946.

The spelling of 642745234 in words is "six hundred forty-two million, seven hundred forty-five thousand, two hundred thirty-four".