1990757 has 4 divisors (see below), whose sum is σ = 1993740. Its totient is φ = 1987776.

The previous prime is 1990753. The next prime is 1990759. The reversal of 1990757 is 7570991.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 516961 + 1473796 = 719^2 + 1214^2 .

It is a cyclic number.

It is not a de Polignac number, because 1990757 - 2² = 1990753 is a prime.

It is a super-2 number, since 2×1990757² = 7926226866098, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1990757.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1990753) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23 + ... + 1995.

It is an arithmetic number, because the mean of its divisors is an integer number (498435).

2^1990757 is an apocalyptic number.

It is an amenable number.

1990757 is a deficient number, since it is larger than the sum of its proper divisors (2983).

1990757 is a wasteful number, since it uses less digits than its factorization.

1990757 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2982.

The product of its (nonzero) digits is 19845, while the sum is 38.

The square root of 1990757 is about 1410.9418839910. The cubic root of 1990757 is about 125.7977143848.

The spelling of 1990757 in words is "one million, nine hundred ninety thousand, seven hundred fifty-seven".