72117786 has 32 divisors (see below), whose sum is σ = 156800448. Its totient is φ = 21980160.

The previous prime is 72117769. The next prime is 72117797. The reversal of 72117786 is 68771127.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4026 + ... + 12666.

It is an arithmetic number, because the mean of its divisors is an integer number (4900014).

Almost surely, 2^72117786 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72117786, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78400224).

72117786 is an abundant number, since it is smaller than the sum of its proper divisors (84682662).

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

72117786 is a wasteful number, since it uses less digits than its factorization.

72117786 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8766.

The product of its digits is 32928, while the sum is 39.

The square root of 72117786 is about 8492.2191446053. The cubic root of 72117786 is about 416.2434972697.

The spelling of 72117786 in words is "seventy-two million, one hundred seventeen thousand, seven hundred eighty-six".