2145187861 has 8 divisors (see below), whose sum is σ = 2166441984. Its totient is φ = 2124002160.

The previous prime is 2145187853. The next prime is 2145187867. The reversal of 2145187861 is 1687815412.

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

It is a cyclic number.

It is not a de Polignac number, because 2145187861 - 2³ = 2145187853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2145187867) 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, 47091 + ... + 80671.

It is an arithmetic number, because the mean of its divisors is an integer number (270805248).

Almost surely, 2^2145187861 is an apocalyptic number.

It is an amenable number.

2145187861 is a deficient number, since it is larger than the sum of its proper divisors (21254123).

2145187861 is a wasteful number, since it uses less digits than its factorization.

2145187861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34211.

The product of its digits is 107520, while the sum is 43.

The square root of 2145187861 is about 46316.1727801424. The cubic root of 2145187861 is about 1289.6992390197.

The spelling of 2145187861 in words is "two billion, one hundred forty-five million, one hundred eighty-seven thousand, eight hundred sixty-one".