1690443225 has 27 divisors (see below), whose sum is σ = 3028876669. Its totient is φ = 901240800.

The previous prime is 1690443203. The next prime is 1690443233. The reversal of 1690443225 is 5223440961.

It is a happy number.

The square root of 1690443225 is 41115.

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

It can be written as a sum of positive squares in 4 ways, for example, as 201100761 + 1489342464 = 14181^2 + 38592^2 .

It is not a de Polignac number, because 1690443225 - 2²⁷ = 1556225497 is a prime.

It is a super-3 number, since 3×1690443225³ (a number of 29 digits) contains 333 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 1690443225.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 615355 + ... + 618095.

Almost surely, 2^1690443225 is an apocalyptic number.

1690443225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1690443225 is the 41115-th square number.

1690443225 is the 20558-th centered octagonal number.

It is an amenable number.

1690443225 is a deficient number, since it is larger than the sum of its proper divisors (1338433444).

1690443225 is an frugal number, since it uses more digits than its factorization.

1690443225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5498 (or 2749 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The cubic root of 1690443225 is about 1191.2425467313.

Multiplying 1690443225 by its sum of digits (36), we get a square (60855956100 = 246690²).

The spelling of 1690443225 in words is "one billion, six hundred ninety million, four hundred forty-three thousand, two hundred twenty-five".