1990725658 has 4 divisors (see below), whose sum is σ = 2986088490. Its totient is φ = 995362828.

The previous prime is 1990725631. The next prime is 1990725679. The reversal of 1990725658 is 8565270991.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1923436449 + 67289209 = 43857^2 + 8203^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 497681413 + ... + 497681416.

Almost surely, 2^1990725658 is an apocalyptic number.

1990725658 is a deficient number, since it is larger than the sum of its proper divisors (995362832).

1990725658 is an equidigital number, since it uses as much as digits as its factorization.

1990725658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 995362831.

The product of its (nonzero) digits is 1360800, while the sum is 52.

The square root of 1990725658 is about 44617.5487672732. The cubic root of 1990725658 is about 1257.9705420497.

The spelling of 1990725658 in words is "one billion, nine hundred ninety million, seven hundred twenty-five thousand, six hundred fifty-eight".