161502978 has 64 divisors (see below), whose sum is σ = 405119232. Its totient is φ = 41783040.

The previous prime is 161502959. The next prime is 161502997. The reversal of 161502978 is 879205161.

It is an interprime number because it is at equal distance from previous prime (161502959) and next prime (161502997).

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 31 ways as a sum of consecutive naturals, for example, 26148 + ... + 31728.

It is an arithmetic number, because the mean of its divisors is an integer number (6329988).

Almost surely, 2^161502978 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161502978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (202559616).

161502978 is an abundant number, since it is smaller than the sum of its proper divisors (243616254).

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

161502978 is a wasteful number, since it uses less digits than its factorization.

161502978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5659.

The product of its (nonzero) digits is 30240, while the sum is 39.

The square root of 161502978 is about 12708.3821944416. The cubic root of 161502978 is about 544.5781074050.

The spelling of 161502978 in words is "one hundred sixty-one million, five hundred two thousand, nine hundred seventy-eight".