66631090 has 16 divisors (see below), whose sum is σ = 123805440. Its totient is φ = 25792560.

The previous prime is 66631087. The next prime is 66631091. The reversal of 66631090 is 9013666.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is not an unprimeable number, because it can be changed into a prime (66631091) 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, 107160 + ... + 107779.

It is an arithmetic number, because the mean of its divisors is an integer number (7737840).

Almost surely, 2^66631090 is an apocalyptic number.

66631090 is a deficient number, since it is larger than the sum of its proper divisors (57174350).

66631090 is a wasteful number, since it uses less digits than its factorization.

66631090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214977.

The product of its (nonzero) digits is 5832, while the sum is 31.

The square root of 66631090 is about 8162.7869015429. The cubic root of 66631090 is about 405.4079920464.

The spelling of 66631090 in words is "sixty-six million, six hundred thirty-one thousand, ninety".