66351438 has 24 divisors (see below), whose sum is σ = 144628848. Its totient is φ = 21983712.

The previous prime is 66351437. The next prime is 66351463. The reversal of 66351438 is 83415366.

66351438 is a `hidden beast` number, since 6 + 635 + 14 + 3 + 8 = 666.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66351431) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8031 + ... + 14042.

It is an arithmetic number, because the mean of its divisors is an integer number (6026202).

Almost surely, 2^66351438 is an apocalyptic number.

66351438 is an abundant number, since it is smaller than the sum of its proper divisors (78277410).

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

66351438 is a wasteful number, since it uses less digits than its factorization.

66351438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22248 (or 22245 counting only the distinct ones).

The product of its digits is 51840, while the sum is 36.

The square root of 66351438 is about 8145.6392014378. The cubic root of 66351438 is about 404.8400282703.

The spelling of 66351438 in words is "sixty-six million, three hundred fifty-one thousand, four hundred thirty-eight".