121225640 has 96 divisors (see below), whose sum is σ = 302800680. Its totient is φ = 43524096.

The previous prime is 121225639. The next prime is 121225661. The reversal of 121225640 is 46522121.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 99640324 + 21585316 = 9982^2 + 4646^2 .

It is a Harshad number since it is a multiple of its sum of digits (23).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 359552 + ... + 359888.

Almost surely, 2^121225640 is an apocalyptic number.

121225640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121225640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (151400340).

121225640 is an abundant number, since it is smaller than the sum of its proper divisors (181575040).

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

121225640 is a wasteful number, since it uses less digits than its factorization.

121225640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 411 (or 384 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 121225640 is about 11010.2515865897. The cubic root of 121225640 is about 494.9160011192.

Adding to 121225640 its reverse (46522121), we get a palindrome (167747761).

The spelling of 121225640 in words is "one hundred twenty-one million, two hundred twenty-five thousand, six hundred forty".