1645942372 has 12 divisors (see below), whose sum is σ = 2880861676. Its totient is φ = 822839040.

The previous prime is 1645942297. The next prime is 1645942409. The reversal of 1645942372 is 2732495461.

It can be written as a sum of positive squares in 2 ways, for example, as 1524590116 + 121352256 = 39046^2 + 11016^2 .

It is a hoax number, since the sum of its digits (43) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1713 + ... + 57400.

Almost surely, 2^1645942372 is an apocalyptic number.

It is an amenable number.

1645942372 is a deficient number, since it is larger than the sum of its proper divisors (1234919304).

1645942372 is a wasteful number, since it uses less digits than its factorization.

1645942372 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66078 (or 66076 counting only the distinct ones).

The product of its digits is 362880, while the sum is 43.

The square root of 1645942372 is about 40570.2153309543. The cubic root of 1645942372 is about 1180.6963169749.

The spelling of 1645942372 in words is "one billion, six hundred forty-five million, nine hundred forty-two thousand, three hundred seventy-two".