66681090 has 64 divisors (see below), whose sum is σ = 203224320. Its totient is φ = 15240960.

The previous prime is 66681079. The next prime is 66681091. The reversal of 66681090 is 9018666.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66681091) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15751 + ... + 19530.

It is an arithmetic number, because the mean of its divisors is an integer number (3175380).

Almost surely, 2^66681090 is an apocalyptic number.

66681090 is an abundant number, since it is smaller than the sum of its proper divisors (136543230).

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

66681090 is a wasteful number, since it uses less digits than its factorization.

66681090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35304 (or 35298 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 66681090 is about 8165.8490066863. The cubic root of 66681090 is about 405.5093728052.

The spelling of 66681090 in words is "sixty-six million, six hundred eighty-one thousand, ninety".