655720690 has 32 divisors (see below), whose sum is σ = 1208520000. Its totient is φ = 256077888.

The previous prime is 655720669. The next prime is 655720693. The reversal of 655720690 is 96027556.

It is a super-2 number, since 2×655720690² = 859939246588152200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (655720693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 84181 + ... + 91639.

It is an arithmetic number, because the mean of its divisors is an integer number (37766250).

Almost surely, 2^655720690 is an apocalyptic number.

655720690 is a deficient number, since it is larger than the sum of its proper divisors (552799310).

655720690 is a wasteful number, since it uses less digits than its factorization.

655720690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7674.

The product of its (nonzero) digits is 113400, while the sum is 40.

The square root of 655720690 is about 25607.0437575289. The cubic root of 655720690 is about 868.7729608341.

The spelling of 655720690 in words is "six hundred fifty-five million, seven hundred twenty thousand, six hundred ninety".