655297890 has 64 divisors (see below), whose sum is σ = 1715212800. Its totient is φ = 159254784.

The previous prime is 655297879. The next prime is 655297919. The reversal of 655297890 is 98792556.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20176 + ... + 41444.

It is an arithmetic number, because the mean of its divisors is an integer number (26800200).

Almost surely, 2^655297890 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 655297890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (857606400).

655297890 is an abundant number, since it is smaller than the sum of its proper divisors (1059914910).

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

655297890 is a wasteful number, since it uses less digits than its factorization.

655297890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21371.

The product of its (nonzero) digits is 1360800, while the sum is 51.

The square root of 655297890 is about 25598.7868853194. The cubic root of 655297890 is about 868.5861962615.

The spelling of 655297890 in words is "six hundred fifty-five million, two hundred ninety-seven thousand, eight hundred ninety".