66512490 has 96 divisors (see below), whose sum is σ = 178573248. Its totient is φ = 15840000.

The previous prime is 66512489. The next prime is 66512497. The reversal of 66512490 is 9421566.

It is a super-2 number, since 2×66512490² = 8847822652000200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66512497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 264865 + ... + 265115.

It is an arithmetic number, because the mean of its divisors is an integer number (1860138).

Almost surely, 2^66512490 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66512490, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89286624).

66512490 is an abundant number, since it is smaller than the sum of its proper divisors (112060758).

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

66512490 is a wasteful number, since it uses less digits than its factorization.

66512490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356 (or 345 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 66512490 is about 8155.5189902299. The cubic root of 66512490 is about 405.1673138905.

The spelling of 66512490 in words is "sixty-six million, five hundred twelve thousand, four hundred ninety".