642154664 has 32 divisors (see below), whose sum is σ = 1266027840. Its totient is φ = 304761600.

The previous prime is 642154621. The next prime is 642154679. The reversal of 642154664 is 466451246.

It is a super-2 number, since 2×642154664² = 824725224993905792, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10784 + ... + 37424.

It is an arithmetic number, because the mean of its divisors is an integer number (39563370).

Almost surely, 2^642154664 is an apocalyptic number.

It is an amenable number.

642154664 is a deficient number, since it is larger than the sum of its proper divisors (623873176).

642154664 is a wasteful number, since it uses less digits than its factorization.

642154664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26801 (or 26797 counting only the distinct ones).

The product of its digits is 138240, while the sum is 38.

The square root of 642154664 is about 25340.7707854359. The cubic root of 642154664 is about 862.7398933350.

The spelling of 642154664 in words is "six hundred forty-two million, one hundred fifty-four thousand, six hundred sixty-four".