161421015 has 32 divisors (see below), whose sum is σ = 308007936. Its totient is φ = 70583040.

The previous prime is 161420993. The next prime is 161421041. The reversal of 161421015 is 510124161.

It is not a de Polignac number, because 161421015 - 2⁷ = 161420887 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 161420982 and 161421000.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 31006 + ... + 35835.

It is an arithmetic number, because the mean of its divisors is an integer number (9625248).

Almost surely, 2^161421015 is an apocalyptic number.

161421015 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

161421015 is a deficient number, since it is larger than the sum of its proper divisors (146586921).

161421015 is a wasteful number, since it uses less digits than its factorization.

161421015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66879.

The product of its (nonzero) digits is 240, while the sum is 21.

The square root of 161421015 is about 12705.1570238230. The cubic root of 161421015 is about 544.4859670847.

Adding to 161421015 its reverse (510124161), we get a palindrome (671545176).

The spelling of 161421015 in words is "one hundred sixty-one million, four hundred twenty-one thousand, fifteen".