161970401 has 4 divisors (see below), whose sum is σ = 162405012. Its totient is φ = 161535792.

The previous prime is 161970371. The next prime is 161970409. The reversal of 161970401 is 104079161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 91393600 + 70576801 = 9560^2 + 8401^2 .

It is a cyclic number.

It is not a de Polignac number, because 161970401 - 2⁶ = 161970337 is a prime.

It is a super-4 number, since 4×161970401⁴ (a number of 34 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161970409) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 216746 + ... + 217491.

It is an arithmetic number, because the mean of its divisors is an integer number (40601253).

Almost surely, 2^161970401 is an apocalyptic number.

It is an amenable number.

161970401 is a deficient number, since it is larger than the sum of its proper divisors (434611).

161970401 is an equidigital number, since it uses as much as digits as its factorization.

161970401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 434610.

The product of its (nonzero) digits is 1512, while the sum is 29.

The square root of 161970401 is about 12726.7592497069. The cubic root of 161970401 is about 545.1029752395.

The spelling of 161970401 in words is "one hundred sixty-one million, nine hundred seventy thousand, four hundred one".