642981243 has 16 divisors (see below), whose sum is σ = 887742720. Its totient is φ = 413466144.

The previous prime is 642981221. The next prime is 642981247. The reversal of 642981243 is 342189246.

It is not a de Polignac number, because 642981243 - 2⁶ = 642981179 is a prime.

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 15 ways as a sum of consecutive naturals, for example, 103380 + ... + 109422.

It is an arithmetic number, because the mean of its divisors is an integer number (55483920).

Almost surely, 2^642981243 is an apocalyptic number.

642981243 is a deficient number, since it is larger than the sum of its proper divisors (244761477).

642981243 is a wasteful number, since it uses less digits than its factorization.

642981243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7298.

The product of its digits is 82944, while the sum is 39.

The square root of 642981243 is about 25357.0748115787. The cubic root of 642981243 is about 863.1099064386.

The spelling of 642981243 in words is "six hundred forty-two million, nine hundred eighty-one thousand, two hundred forty-three".