172978247 has 8 divisors (see below), whose sum is σ = 197242416. Its totient is φ = 150279552.

The previous prime is 172978237. The next prime is 172978259. The reversal of 172978247 is 742879271.

172978247 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 172978247 - 2⁴ = 172978231 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172978217) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 391133 + ... + 391574.

It is an arithmetic number, because the mean of its divisors is an integer number (24655302).

Almost surely, 2^172978247 is an apocalyptic number.

172978247 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

172978247 is a deficient number, since it is larger than the sum of its proper divisors (24264169).

172978247 is a wasteful number, since it uses less digits than its factorization.

172978247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 782737.

The product of its digits is 395136, while the sum is 47.

The square root of 172978247 is about 13152.1194869876. The cubic root of 172978247 is about 557.1821102584.

The spelling of 172978247 in words is "one hundred seventy-two million, nine hundred seventy-eight thousand, two hundred forty-seven".