642931481 has 8 divisors (see below), whose sum is σ = 677524800. Its totient is φ = 608413680.

The previous prime is 642931451. The next prime is 642931543. The reversal of 642931481 is 184139246.

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 642931481 - 2⁶ = 642931417 is a prime.

It is a super-2 number, since 2×642931481² = 826721778521706722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (642931451) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 950 + ... + 35871.

It is an arithmetic number, because the mean of its divisors is an integer number (84690600).

Almost surely, 2^642931481 is an apocalyptic number.

It is an amenable number.

642931481 is a deficient number, since it is larger than the sum of its proper divisors (34593319).

642931481 is a wasteful number, since it uses less digits than its factorization.

642931481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37759.

The product of its digits is 41472, while the sum is 38.

The square root of 642931481 is about 25356.0935674248. The cubic root of 642931481 is about 863.0876397531.

The spelling of 642931481 in words is "six hundred forty-two million, nine hundred thirty-one thousand, four hundred eighty-one".