66251290 has 64 divisors (see below), whose sum is σ = 145094400. Its totient is φ = 21275136.

The previous prime is 66251287. The next prime is 66251299. The reversal of 66251290 is 9215266.

It is not an unprimeable number, because it can be changed into a prime (66251299) 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, 144742 + ... + 145198.

It is an arithmetic number, because the mean of its divisors is an integer number (2267100).

Almost surely, 2^66251290 is an apocalyptic number.

66251290 is an abundant number, since it is smaller than the sum of its proper divisors (78843110).

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

66251290 is a wasteful number, since it uses less digits than its factorization.

66251290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 599.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 66251290 is about 8139.4895417342. The cubic root of 66251290 is about 404.6362430125.

The spelling of 66251290 in words is "sixty-six million, two hundred fifty-one thousand, two hundred ninety".