1990429 has 10 divisors (see below), whose sum is σ = 2324830. Its totient is φ = 1704024.

The previous prime is 1990381. The next prime is 1990433. The reversal of 1990429 is 9240991.

It can be written as a sum of positive squares in only one way, i.e., 1750329 + 240100 = 1323^2 + 490^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1990429 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1990394 and 1990403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1990229) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 1987 + ... + 2815.

It is an arithmetic number, because the mean of its divisors is an integer number (232483).

2^1990429 is an apocalyptic number.

It is an amenable number.

1990429 is a deficient number, since it is larger than the sum of its proper divisors (334401).

1990429 is an frugal number, since it uses more digits than its factorization.

1990429 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 857 (or 836 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 34.

The square root of 1990429 is about 1410.8256447910. The cubic root of 1990429 is about 125.7908051342.

The spelling of 1990429 in words is "one million, nine hundred ninety thousand, four hundred twenty-nine".