121161621 has 16 divisors (see below), whose sum is σ = 185105024. Its totient is φ = 69056064.

The previous prime is 121161619. The next prime is 121161637. The reversal of 121161621 is 126161121.

It is not a de Polignac number, because 121161621 - 2¹ = 121161619 is a prime.

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

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121161121) 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, 1071 + ... + 15603.

It is an arithmetic number, because the mean of its divisors is an integer number (11569064).

Almost surely, 2^121161621 is an apocalyptic number.

It is an amenable number.

121161621 is a deficient number, since it is larger than the sum of its proper divisors (63943403).

121161621 is a wasteful number, since it uses less digits than its factorization.

121161621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14940.

The product of its digits is 144, while the sum is 21.

The square root of 121161621 is about 11007.3439575585. The cubic root of 121161621 is about 494.8288644196.

The spelling of 121161621 in words is "one hundred twenty-one million, one hundred sixty-one thousand, six hundred twenty-one".