78172000 has 48 divisors (see below), whose sum is σ = 192078432. Its totient is φ = 31267200.

The previous prime is 78171997. The next prime is 78172013. The reversal of 78172000 is 27187.

It is a happy number.

It is a super-3 number, since 3×78172000³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5772 + ... + 13771.

It is an arithmetic number, because the mean of its divisors is an integer number (4001634).

Almost surely, 2^78172000 is an apocalyptic number.

It is an amenable number.

78172000 is an abundant number, since it is smaller than the sum of its proper divisors (113906432).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78172000 is a wasteful number, since it uses less digits than its factorization.

78172000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19568 (or 19550 counting only the distinct ones).

The product of its (nonzero) digits is 784, while the sum is 25.

The square root of 78172000 is about 8841.4930865776. The cubic root of 78172000 is about 427.5796962780.

Adding to 78172000 its reverse (27187), we get a palindrome (78199187).

The spelling of 78172000 in words is "seventy-eight million, one hundred seventy-two thousand".