121649580 has 288 divisors, whose sum is σ = 432875520. Its totient is φ = 28304640.

The previous prime is 121649579. The next prime is 121649581. The reversal of 121649580 is 85946121.

121649580 is a `hidden beast` number, since 1 + 2 + 1 + 649 + 5 + 8 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (121649579) and next prime (121649581).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121649581) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2829039 + ... + 2829081.

It is an arithmetic number, because the mean of its divisors is an integer number (1503040).

Almost surely, 2^121649580 is an apocalyptic number.

121649580 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 121649580, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (216437760).

121649580 is an abundant number, since it is smaller than the sum of its proper divisors (311225940).

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

121649580 is a wasteful number, since it uses less digits than its factorization.

121649580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118 (or 97 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 121649580 is about 11029.4868420974. The cubic root of 121649580 is about 495.4922559488.

The spelling of 121649580 in words is "one hundred twenty-one million, six hundred forty-nine thousand, five hundred eighty".