1990917 has 12 divisors (see below), whose sum is σ = 2896140. Its totient is φ = 1317888.

The previous prime is 1990907. The next prime is 1990927. The reversal of 1990917 is 7190991.

It is an interprime number because it is at equal distance from previous prime (1990907) and next prime (1990927).

It can be written as a sum of positive squares in 2 ways, for example, as 224676 + 1766241 = 474^2 + 1329^2 .

It is not a de Polignac number, because 1990917 - 2⁸ = 1990661 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1990907) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 709 + ... + 2117.

It is an arithmetic number, because the mean of its divisors is an integer number (241345).

2^1990917 is an apocalyptic number.

It is an amenable number.

1990917 is a deficient number, since it is larger than the sum of its proper divisors (905223).

1990917 is a wasteful number, since it uses less digits than its factorization.

1990917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1572 (or 1569 counting only the distinct ones).

The product of its (nonzero) digits is 5103, while the sum is 36.

The square root of 1990917 is about 1410.9985825648. The cubic root of 1990917 is about 125.8010844755.

The spelling of 1990917 in words is "one million, nine hundred ninety thousand, nine hundred seventeen".