642981245 has 8 divisors (see below), whose sum is σ = 783093984. Its totient is φ = 506707344.

The previous prime is 642981221. The next prime is 642981247. The reversal of 642981245 is 542189246.

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

It is a cyclic number.

It is not a de Polignac number, because 642981245 - 2²⁸ = 374545789 is a prime.

It is a super-3 number, since 3×642981245³ (a number of 27 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642981247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 959339 + ... + 960008.

It is an arithmetic number, because the mean of its divisors is an integer number (97886748).

Almost surely, 2^642981245 is an apocalyptic number.

It is an amenable number.

642981245 is a deficient number, since it is larger than the sum of its proper divisors (140112739).

642981245 is a wasteful number, since it uses less digits than its factorization.

642981245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1919419.

The product of its digits is 138240, while the sum is 41.

The square root of 642981245 is about 25357.0748510154. The cubic root of 642981245 is about 863.1099073335.

The spelling of 642981245 in words is "six hundred forty-two million, nine hundred eighty-one thousand, two hundred forty-five".