121660640 has 48 divisors (see below), whose sum is σ = 288943200. Its totient is φ = 48407040.

The previous prime is 121660633. The next prime is 121660681. The reversal of 121660640 is 46066121.

It is a happy number.

It is a super-2 number, since 2×121660640² = 29602622650419200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29930 + ... + 33750.

It is an arithmetic number, because the mean of its divisors is an integer number (6019650).

Almost surely, 2^121660640 is an apocalyptic number.

121660640 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 121660640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144471600).

121660640 is an abundant number, since it is smaller than the sum of its proper divisors (167282560).

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

121660640 is a wasteful number, since it uses less digits than its factorization.

121660640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4035 (or 4027 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 121660640 is about 11029.9882139556. The cubic root of 121660640 is about 495.5072716967.

The spelling of 121660640 in words is "one hundred twenty-one million, six hundred sixty thousand, six hundred forty".