655690 has 64 divisors (see below), whose sum is σ = 1555200. Its totient is φ = 193536.

The previous prime is 655687. The next prime is 655693. The reversal of 655690 is 96556.

655690 = T₂₄₆ + T₂₄₇ + ... + T₂₆₅.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (655687) and next prime (655693).

It is a super-2 number, since 2×655690² = 859858752200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (655693) 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, 22596 + ... + 22624.

It is an arithmetic number, because the mean of its divisors is an integer number (24300).

2⁶⁵⁵⁶⁹⁰ is an apocalyptic number.

655690 is an abundant number, since it is smaller than the sum of its proper divisors (899510).

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

655690 is a wasteful number, since it uses less digits than its factorization.

655690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79.

The product of its (nonzero) digits is 8100, while the sum is 31.

The square root of 655690 is about 809.7468740292. The cubic root of 655690 is about 86.8759406761.

It can be divided in two parts, 6 and 55690, that added together give a square (55696 = 236²).

The spelling of 655690 in words is "six hundred fifty-five thousand, six hundred ninety".