165900780 has 144 divisors (see below), whose sum is σ = 534643200. Its totient is φ = 41523840.

The previous prime is 165900769. The next prime is 165900781. The reversal of 165900780 is 87009561.

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

It is not an unprimeable number, because it can be changed into a prime (165900781) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 612045 + ... + 612315.

It is an arithmetic number, because the mean of its divisors is an integer number (3712800).

Almost surely, 2^165900780 is an apocalyptic number.

165900780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 165900780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (267321600).

165900780 is an abundant number, since it is smaller than the sum of its proper divisors (368742420).

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

165900780 is a wasteful number, since it uses less digits than its factorization.

165900780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 484 (or 479 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 36.

The square root of 165900780 is about 12880.2476684263. The cubic root of 165900780 is about 549.4769462562.

The spelling of 165900780 in words is "one hundred sixty-five million, nine hundred thousand, seven hundred eighty".