66401236 has 24 divisors (see below), whose sum is σ = 130195296. Its totient is φ = 29365920.

The previous prime is 66401227. The next prime is 66401239. The reversal of 66401236 is 63210466.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66401239) 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, 18766 + ... + 22021.

It is an arithmetic number, because the mean of its divisors is an integer number (5424804).

Almost surely, 2^66401236 is an apocalyptic number.

It is an amenable number.

66401236 is a deficient number, since it is larger than the sum of its proper divisors (63794060).

66401236 is a wasteful number, since it uses less digits than its factorization.

66401236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40839 (or 40837 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 28.

The square root of 66401236 is about 8148.6953556996. The cubic root of 66401236 is about 404.9412829574.

The spelling of 66401236 in words is "sixty-six million, four hundred one thousand, two hundred thirty-six".