1897811139 has 16 divisors (see below), whose sum is σ = 2892815360. Its totient is φ = 1084121280.

The previous prime is 1897811131. The next prime is 1897811161. The reversal of 1897811139 is 9311187981.

It is not a de Polignac number, because 1897811139 - 2³ = 1897811131 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1897811131) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 63807 + ... + 88695.

It is an arithmetic number, because the mean of its divisors is an integer number (180800960).

Almost surely, 2^1897811139 is an apocalyptic number.

1897811139 is a deficient number, since it is larger than the sum of its proper divisors (995004221).

1897811139 is a wasteful number, since it uses less digits than its factorization.

1897811139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28530.

The product of its digits is 108864, while the sum is 48.

The square root of 1897811139 is about 43563.8742423123. The cubic root of 1897811139 is about 1238.0865256802.

The spelling of 1897811139 in words is "one billion, eight hundred ninety-seven million, eight hundred eleven thousand, one hundred thirty-nine".