1655990 has 32 divisors (see below), whose sum is σ = 3495744. Its totient is φ = 552960.

The previous prime is 1655981. The next prime is 1655999. The reversal of 1655990 is 995561.

It is an interprime number because it is at equal distance from previous prime (1655981) and next prime (1655999).

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 1655990.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1655999) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2582 + ... + 3158.

It is an arithmetic number, because the mean of its divisors is an integer number (109242).

2^1655990 is an apocalyptic number.

1655990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1655990 is an abundant number, since it is smaller than the sum of its proper divisors (1839754).

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

1655990 is a wasteful number, since it uses less digits than its factorization.

1655990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 632.

The product of its (nonzero) digits is 12150, while the sum is 35.

The square root of 1655990 is about 1286.8527499291. The cubic root of 1655990 is about 118.3093958501.

The spelling of 1655990 in words is "one million, six hundred fifty-five thousand, nine hundred ninety".