161221470 has 32 divisors (see below), whose sum is σ = 387268992. Its totient is φ = 42954912.

The previous prime is 161221409. The next prime is 161221477. The reversal of 161221470 is 74122161.

161221470 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 161221470.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161221477) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 58749 + ... + 61431.

It is an arithmetic number, because the mean of its divisors is an integer number (12102156).

Almost surely, 2^161221470 is an apocalyptic number.

161221470 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161221470 is an abundant number, since it is smaller than the sum of its proper divisors (226047522).

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

161221470 is a wasteful number, since it uses less digits than its factorization.

161221470 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4696.

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 161221470 is about 12697.3016818535. The cubic root of 161221470 is about 544.2615141677.

The spelling of 161221470 in words is "one hundred sixty-one million, two hundred twenty-one thousand, four hundred seventy".