1990621594 has 24 divisors (see below), whose sum is σ = 3294322812. Its totient is φ = 901405440.

The previous prime is 1990621573. The next prime is 1990621637. The reversal of 1990621594 is 4951260991.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 515063025 + 1475558569 = 22695^2 + 38413^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 37647 + ... + 73474.

Almost surely, 2^1990621594 is an apocalyptic number.

1990621594 is a deficient number, since it is larger than the sum of its proper divisors (1303701218).

1990621594 is a wasteful number, since it uses less digits than its factorization.

1990621594 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111202 (or 111189 counting only the distinct ones).

The product of its (nonzero) digits is 174960, while the sum is 46.

The square root of 1990621594 is about 44616.3825741173. The cubic root of 1990621594 is about 1257.9486217804.

The spelling of 1990621594 in words is "one billion, nine hundred ninety million, six hundred twenty-one thousand, five hundred ninety-four".