102155215 has 4 divisors (see below), whose sum is σ = 122586264. Its totient is φ = 81724168.

The previous prime is 102155203. The next prime is 102155219. The reversal of 102155215 is 512551201.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 102155215 - 2⁷ = 102155087 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102155219) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10215517 + ... + 10215526.

It is an arithmetic number, because the mean of its divisors is an integer number (30646566).

Almost surely, 2^102155215 is an apocalyptic number.

102155215 is a deficient number, since it is larger than the sum of its proper divisors (20431049).

102155215 is an equidigital number, since it uses as much as digits as its factorization.

102155215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20431048.

The product of its (nonzero) digits is 500, while the sum is 22.

The square root of 102155215 is about 10107.1863048031. The cubic root of 102155215 is about 467.4697512528.

The spelling of 102155215 in words is "one hundred two million, one hundred fifty-five thousand, two hundred fifteen".