121947840 has 336 divisors, whose sum is σ = 502115328. Its totient is φ = 26560512.

The previous prime is 121947829. The next prime is 121947853. The reversal of 121947840 is 48749121.

It is a tau number, because it is divible by the number of its divisors (336).

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

It is a junction number, because it is equal to n+sod(n) for n = 121947795 and 121947804.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 463549 + ... + 463811.

Almost surely, 2^121947840 is an apocalyptic number.

121947840 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 121947840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (251057664).

121947840 is an abundant number, since it is smaller than the sum of its proper divisors (380167488).

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

121947840 is a wasteful number, since it uses less digits than its factorization.

121947840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316 (or 303 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 121947840 is about 11042.9995925020. Note that the first 3 decimals coincide. The cubic root of 121947840 is about 495.8968741549.

The spelling of 121947840 in words is "one hundred twenty-one million, nine hundred forty-seven thousand, eight hundred forty".