642901439 has 4 divisors (see below), whose sum is σ = 643354656. Its totient is φ = 642448224.

The previous prime is 642901433. The next prime is 642901459. The reversal of 642901439 is 934109246.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642901439 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642901433) 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, 224474 + ... + 227319.

It is an arithmetic number, because the mean of its divisors is an integer number (160838664).

Almost surely, 2^642901439 is an apocalyptic number.

642901439 is a deficient number, since it is larger than the sum of its proper divisors (453217).

642901439 is a wasteful number, since it uses less digits than its factorization.

642901439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 453216.

The product of its (nonzero) digits is 46656, while the sum is 38.

The square root of 642901439 is about 25355.5011585257. The cubic root of 642901439 is about 863.0741964944.

The spelling of 642901439 in words is "six hundred forty-two million, nine hundred one thousand, four hundred thirty-nine".