1897137861 has 8 divisors (see below), whose sum is σ = 2572390560. Its totient is φ = 1243321872.

The previous prime is 1897137857. The next prime is 1897137883. The reversal of 1897137861 is 1687317981.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1897137861 - 2² = 1897137857 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1897137161) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5358970 + ... + 5359323.

It is an arithmetic number, because the mean of its divisors is an integer number (321548820).

Almost surely, 2^1897137861 is an apocalyptic number.

It is an amenable number.

1897137861 is a deficient number, since it is larger than the sum of its proper divisors (675252699).

1897137861 is a wasteful number, since it uses less digits than its factorization.

1897137861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10718355.

The product of its digits is 508032, while the sum is 51.

The square root of 1897137861 is about 43556.1460760706. The cubic root of 1897137861 is about 1237.9400982167.

The spelling of 1897137861 in words is "one billion, eight hundred ninety-seven million, one hundred thirty-seven thousand, eight hundred sixty-one".