172664945 has 4 divisors (see below), whose sum is σ = 207197940. Its totient is φ = 138131952.

The previous prime is 172664923. The next prime is 172664959. The reversal of 172664945 is 549466271.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 549466271 = 719 ⋅764209.

It can be written as a sum of positive squares in 2 ways, for example, as 33825856 + 138839089 = 5816^2 + 11783^2 .

It is a cyclic number.

It is not a de Polignac number, because 172664945 - 2⁶ = 172664881 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 172664896 and 172664905.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17266490 + ... + 17266499.

It is an arithmetic number, because the mean of its divisors is an integer number (51799485).

Almost surely, 2^172664945 is an apocalyptic number.

It is an amenable number.

172664945 is a deficient number, since it is larger than the sum of its proper divisors (34532995).

172664945 is an equidigital number, since it uses as much as digits as its factorization.

172664945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34532994.

The product of its digits is 362880, while the sum is 44.

The square root of 172664945 is about 13140.2033850318. The cubic root of 172664945 is about 556.8455134676.

The spelling of 172664945 in words is "one hundred seventy-two million, six hundred sixty-four thousand, nine hundred forty-five".