161355780 has 96 divisors (see below), whose sum is σ = 513744000. Its totient is φ = 42021504.

The previous prime is 161355773. The next prime is 161355827. The reversal of 161355780 is 87553161.

161355780 is a `hidden beast` number, since 16 + 13 + 557 + 80 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19746 + ... + 26694.

It is an arithmetic number, because the mean of its divisors is an integer number (5351500).

Almost surely, 2^161355780 is an apocalyptic number.

161355780 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 161355780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (256872000).

161355780 is an abundant number, since it is smaller than the sum of its proper divisors (352388220).

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

161355780 is a wasteful number, since it uses less digits than its factorization.

161355780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7010 (or 7002 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 36.

The square root of 161355780 is about 12702.5894997831. The cubic root of 161355780 is about 544.4126095813.

The spelling of 161355780 in words is "one hundred sixty-one million, three hundred fifty-five thousand, seven hundred eighty".