83217780 has 72 divisors (see below), whose sum is σ = 261791712. Its totient is φ = 22190112.

The previous prime is 83217727. The next prime is 83217793. The reversal of 83217780 is 8771238.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3702 + ... + 13421.

It is an arithmetic number, because the mean of its divisors is an integer number (3635996).

Almost surely, 2^83217780 is an apocalyptic number.

It is an amenable number.

83217780 is an abundant number, since it is smaller than the sum of its proper divisors (178573932).

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

83217780 is a wasteful number, since it uses less digits than its factorization.

83217780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17147 (or 17133 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 36.

The square root of 83217780 is about 9122.3779794525. The cubic root of 83217780 is about 436.5882487106.

The spelling of 83217780 in words is "eighty-three million, two hundred seventeen thousand, seven hundred eighty".