1897921837 has 32 divisors (see below), whose sum is σ = 2430362880. Its totient is φ = 1442810880.

The previous prime is 1897921813. The next prime is 1897921841. The reversal of 1897921837 is 7381297981.

It is not a de Polignac number, because 1897921837 - 2²⁷ = 1763704109 is a prime.

It is a super-2 number, since 2×1897921837² = 7204214598722909138, which contains 22 as substring.

It is a Smith number, since the sum of its digits (55) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1897921847) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 443287 + ... + 447547.

It is an arithmetic number, because the mean of its divisors is an integer number (75948840).

Almost surely, 2^1897921837 is an apocalyptic number.

1897921837 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

1897921837 is a deficient number, since it is larger than the sum of its proper divisors (532441043).

1897921837 is a wasteful number, since it uses less digits than its factorization.

1897921837 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4501.

The product of its digits is 1524096, while the sum is 55.

The square root of 1897921837 is about 43565.1447489848. The cubic root of 1897921837 is about 1238.1105974533.

The spelling of 1897921837 in words is "one billion, eight hundred ninety-seven million, nine hundred twenty-one thousand, eight hundred thirty-seven".