121947898553856 has 400 divisors, whose sum is σ = 369103087189584. Its totient is φ = 40077829472256.

The previous prime is 121947898553839. The next prime is 121947898553861. The reversal of 121947898553856 is 658355898749121.

121947898553856 is a `hidden beast` number, since 1 + 2 + 1 + 9 + 4 + 7 + 8 + 9 + 8 + 553 + 8 + 56 = 666.

It is a super-2 number, since 2×121947898553856² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 11029016680 + ... + 11029027736.

Almost surely, 2^{121947898553856} is an apocalyptic number.

121947898553856 is a gapful number since it is divisible by the number (16) 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 121947898553856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (184551543594792).

121947898553856 is an abundant number, since it is smaller than the sum of its proper divisors (247155188635728).

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

121947898553856 is an equidigital number, since it uses as much as digits as its factorization.

121947898553856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14803 (or 14778 counting only the distinct ones).

The product of its digits is 5225472000, while the sum is 81.

The spelling of 121947898553856 in words is "one hundred twenty-one trillion, nine hundred forty-seven billion, eight hundred ninety-eight million, five hundred fifty-three thousand, eight hundred fifty-six".