1988690 has 32 divisors (see below), whose sum is σ = 3965760. Its totient is φ = 712000.

The previous prime is 1988689. The next prime is 1988699. The reversal of 1988690 is 968891.

It is a super-2 number, since 2×1988690² = 7909775832200, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1988699) 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, 11021 + ... + 11199.

It is an arithmetic number, because the mean of its divisors is an integer number (123930).

2^1988690 is an apocalyptic number.

1988690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1988690 is a deficient number, since it is larger than the sum of its proper divisors (1977070).

1988690 is a wasteful number, since it uses less digits than its factorization.

1988690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298.

The product of its (nonzero) digits is 31104, while the sum is 41.

The square root of 1988690 is about 1410.2092043381. The cubic root of 1988690 is about 125.7541607815.

It can be divided in two parts, 198 and 8690, that added together give a palindrome (8888).

The spelling of 1988690 in words is "one million, nine hundred eighty-eight thousand, six hundred ninety".