2135991897 has 64 divisors (see below), whose sum is σ = 3544934400. Its totient is φ = 1262096640.

The previous prime is 2135991881. The next prime is 2135991929. The reversal of 2135991897 is 7981995312.

It is not a de Polignac number, because 2135991897 - 2⁴ = 2135991881 is a prime.

It is a super-2 number, since 2×2135991897² = 9124922768099317218, which contains 22 as substring.

Its product of digits (1224720) is a multiple of the sum of its prime factors (1215).

It is not an unprimeable number, because it can be changed into a prime (2135991817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2269447 + ... + 2270387.

It is an arithmetic number, because the mean of its divisors is an integer number (55389600).

Almost surely, 2^2135991897 is an apocalyptic number.

2135991897 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

2135991897 is a deficient number, since it is larger than the sum of its proper divisors (1408942503).

2135991897 is a wasteful number, since it uses less digits than its factorization.

2135991897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1215 (or 1209 counting only the distinct ones).

The product of its digits is 1224720, while the sum is 54.

The square root of 2135991897 is about 46216.7923703063. The cubic root of 2135991897 is about 1287.8537106158.

It can be divided in two parts, 213599 and 1897, that added together give a triangular number (215496 = T₆₅₆).

The spelling of 2135991897 in words is "two billion, one hundred thirty-five million, nine hundred ninety-one thousand, eight hundred ninety-seven".