102172945 has 32 divisors (see below), whose sum is σ = 148389120. Its totient is φ = 66044160.

The previous prime is 102172933. The next prime is 102172949. The reversal of 102172945 is 549271201.

It is not a de Polignac number, because 102172945 - 2¹¹ = 102170897 is a prime.

It is not an unprimeable number, because it can be changed into a prime (102172949) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 42475 + ... + 44815.

It is an arithmetic number, because the mean of its divisors is an integer number (4637160).

Almost surely, 2^102172945 is an apocalyptic number.

It is an amenable number.

102172945 is a deficient number, since it is larger than the sum of its proper divisors (46216175).

102172945 is a wasteful number, since it uses less digits than its factorization.

102172945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2425.

The product of its (nonzero) digits is 5040, while the sum is 31.

The square root of 102172945 is about 10108.0633654524. The cubic root of 102172945 is about 467.4967942815.

The spelling of 102172945 in words is "one hundred two million, one hundred seventy-two thousand, nine hundred forty-five".