1990432823929 has 9 divisors (see below), whose sum is σ = 2187848178831. Its totient is φ = 1809470277120.

The previous prime is 1990432823917. The next prime is 1990432823933. The reversal of 1990432823929 is 9293282340991.

The square root of 1990432823929 is 1410827.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1897134343225 + 93298480704 = 1377365^2 + 305448^2 .

It is not a de Polignac number, because 1990432823929 - 2¹³ = 1990432815737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1990432823959) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 15454969 + ... + 15583225.

Almost surely, 2^{1990432823929} is an apocalyptic number.

1990432823929 is the 1410827-th square number.

1990432823929 is the 705414-th centered octagonal number.

It is an amenable number.

1990432823929 is a deficient number, since it is larger than the sum of its proper divisors (197415354902).

1990432823929 is an frugal number, since it uses more digits than its factorization.

1990432823929 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256536 (or 128268 counting only the distinct ones).

The product of its (nonzero) digits is 15116544, while the sum is 61.

The spelling of 1990432823929 in words is "one trillion, nine hundred ninety billion, four hundred thirty-two million, eight hundred twenty-three thousand, nine hundred twenty-nine".