42639966 has 32 divisors (see below), whose sum is σ = 95097600. Its totient is φ = 14162040.

The previous prime is 42639937. The next prime is 42639977. The reversal of 42639966 is 66993624.

42639966 is a `hidden beast` number, since 4 + 2 + 639 + 9 + 6 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15525 + ... + 18063.

It is an arithmetic number, because the mean of its divisors is an integer number (2971800).

Almost surely, 2^42639966 is an apocalyptic number.

42639966 is an abundant number, since it is smaller than the sum of its proper divisors (52457634).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

42639966 is a wasteful number, since it uses less digits than its factorization.

42639966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2861 (or 2855 counting only the distinct ones).

The product of its digits is 419904, while the sum is 45.

The square root of 42639966 is about 6529.9284835287. The cubic root of 42639966 is about 349.3592794942.

The spelling of 42639966 in words is "forty-two million, six hundred thirty-nine thousand, nine hundred sixty-six".