642988930 has 8 divisors (see below), whose sum is σ = 1157380092. Its totient is φ = 257195568.

The previous prime is 642988921. The next prime is 642988939. The reversal of 642988930 is 39889246.

It is an interprime number because it is at equal distance from previous prime (642988921) and next prime (642988939).

It can be written as a sum of positive squares in 2 ways, for example, as 642166281 + 822649 = 25341^2 + 907^2 .

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

It is not an unprimeable number, because it can be changed into a prime (642988939) 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, 32149437 + ... + 32149456.

Almost surely, 2^642988930 is an apocalyptic number.

642988930 is a deficient number, since it is larger than the sum of its proper divisors (514391162).

642988930 is a wasteful number, since it uses less digits than its factorization.

642988930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64298900.

The product of its (nonzero) digits is 746496, while the sum is 49.

The square root of 642988930 is about 25357.2263861803. The cubic root of 642988930 is about 863.1133459891.

It can be divided in two parts, 6429 and 88930, that added together give a palindrome (95359).

The spelling of 642988930 in words is "six hundred forty-two million, nine hundred eighty-eight thousand, nine hundred thirty".