2151538109 has 12 divisors (see below), whose sum is σ = 2505694464. Its totient is φ = 1842049944.

The previous prime is 2151538091. The next prime is 2151538111. The reversal of 2151538109 is 9018351512.

It is a de Polignac number, because none of the positive numbers 2^k-2151538109 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2151537109) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18404 + ... + 68130.

It is an arithmetic number, because the mean of its divisors is an integer number (208807872).

Almost surely, 2^2151538109 is an apocalyptic number.

It is an amenable number.

2151538109 is a deficient number, since it is larger than the sum of its proper divisors (354156355).

2151538109 is an equidigital number, since it uses as much as digits as its factorization.

2151538109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50624 (or 50617 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 35.

The square root of 2151538109 is about 46384.6753680566. The cubic root of 2151538109 is about 1290.9705871828.

The spelling of 2151538109 in words is "two billion, one hundred fifty-one million, five hundred thirty-eight thousand, one hundred nine".