1897951645 has 16 divisors (see below), whose sum is σ = 2302709760. Its totient is φ = 1501622784.

The previous prime is 1897951639. The next prime is 1897951681. The reversal of 1897951645 is 5461597981.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1897951645 - 2³ = 1897951637 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 476452 + ... + 480418.

It is an arithmetic number, because the mean of its divisors is an integer number (143919360).

Almost surely, 2^1897951645 is an apocalyptic number.

It is an amenable number.

1897951645 is a deficient number, since it is larger than the sum of its proper divisors (404758115).

1897951645 is a wasteful number, since it uses less digits than its factorization.

1897951645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5004.

The product of its digits is 2721600, while the sum is 55.

The square root of 1897951645 is about 43565.4868559965. The cubic root of 1897951645 is about 1238.1170791757.

The spelling of 1897951645 in words is "one billion, eight hundred ninety-seven million, nine hundred fifty-one thousand, six hundred forty-five".