121661625 has 16 divisors (see below), whose sum is σ = 202445568. Its totient is φ = 64886000.

The previous prime is 121661623. The next prime is 121661647. The reversal of 121661625 is 526166121.

It is not a de Polignac number, because 121661625 - 2¹ = 121661623 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 121661592 and 121661601.

It is not an unprimeable number, because it can be changed into a prime (121661623) 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, 161841 + ... + 162590.

It is an arithmetic number, because the mean of its divisors is an integer number (12652848).

Almost surely, 2^121661625 is an apocalyptic number.

121661625 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

121661625 is a deficient number, since it is larger than the sum of its proper divisors (80783943).

121661625 is an equidigital number, since it uses as much as digits as its factorization.

121661625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324449 (or 324439 counting only the distinct ones).

The product of its digits is 4320, while the sum is 30.

The square root of 121661625 is about 11030.0328648649. The cubic root of 121661625 is about 495.5086089502.

The spelling of 121661625 in words is "one hundred twenty-one million, six hundred sixty-one thousand, six hundred twenty-five".