172009780 has 24 divisors (see below), whose sum is σ = 367345440. Its totient is φ = 67637280.

The previous prime is 172009771. The next prime is 172009807. The reversal of 172009780 is 87900271.

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, 71706 + ... + 74065.

It is an arithmetic number, because the mean of its divisors is an integer number (15306060).

Almost surely, 2^172009780 is an apocalyptic number.

172009780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

172009780 is an abundant number, since it is smaller than the sum of its proper divisors (195335660).

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

172009780 is a wasteful number, since it uses less digits than its factorization.

172009780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145839 (or 145837 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 34.

The square root of 172009780 is about 13115.2499023084. The cubic root of 172009780 is about 556.1403170516.

The spelling of 172009780 in words is "one hundred seventy-two million, nine thousand, seven hundred eighty".