1897921838 has 16 divisors (see below), whose sum is σ = 2902236480. Its totient is φ = 930530016.

The previous prime is 1897921813. The next prime is 1897921841. The reversal of 1897921838 is 8381297981.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 238508 + ... + 246336.

It is an arithmetic number, because the mean of its divisors is an integer number (181389780).

Almost surely, 2^1897921838 is an apocalyptic number.

1897921838 is a deficient number, since it is larger than the sum of its proper divisors (1004314642).

1897921838 is a wasteful number, since it uses less digits than its factorization.

1897921838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10171.

The product of its digits is 1741824, while the sum is 56.

The square root of 1897921838 is about 43565.1447604619. The cubic root of 1897921838 is about 1238.1105976708.

The spelling of 1897921838 in words is "one billion, eight hundred ninety-seven million, nine hundred twenty-one thousand, eight hundred thirty-eight".