2151820215 has 64 divisors (see below), whose sum is σ = 3874759680. Its totient is φ = 1132963200.

The previous prime is 2151820207. The next prime is 2151820247. The reversal of 2151820215 is 5120281512.

It is a happy number.

It is not a de Polignac number, because 2151820215 - 2³ = 2151820207 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 5768769 + ... + 5769141.

It is an arithmetic number, because the mean of its divisors is an integer number (60543120).

Almost surely, 2^2151820215 is an apocalyptic number.

2151820215 is a deficient number, since it is larger than the sum of its proper divisors (1722939465).

2151820215 is a wasteful number, since it uses less digits than its factorization.

2151820215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 821 (or 815 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 27.

The square root of 2151820215 is about 46387.7162080653. The cubic root of 2151820215 is about 1291.0270080027.

The spelling of 2151820215 in words is "two billion, one hundred fifty-one million, eight hundred twenty thousand, two hundred fifteen".