102156217 has 16 divisors (see below), whose sum is σ = 109771200. Its totient is φ = 94789440.

The previous prime is 102156211. The next prime is 102156221. The reversal of 102156217 is 712651201.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-102156217 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 102156191 and 102156200.

It is not an unprimeable number, because it can be changed into a prime (102156211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 221367 + ... + 221827.

It is an arithmetic number, because the mean of its divisors is an integer number (6860700).

Almost surely, 2^102156217 is an apocalyptic number.

It is an amenable number.

102156217 is a deficient number, since it is larger than the sum of its proper divisors (7614983).

102156217 is a wasteful number, since it uses less digits than its factorization.

102156217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 696.

The product of its (nonzero) digits is 840, while the sum is 25.

The square root of 102156217 is about 10107.2358733731. The cubic root of 102156217 is about 467.4712796563.

The spelling of 102156217 in words is "one hundred two million, one hundred fifty-six thousand, two hundred seventeen".