121550400400 has 240 divisors, whose sum is σ = 345604629888. Its totient is φ = 40499712000.

The previous prime is 121550400347. The next prime is 121550400431. The reversal of 121550400400 is 4004055121.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7828645 + ... + 7844155.

Almost surely, 2^121550400400 is an apocalyptic number.

121550400400 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 121550400400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (172802314944).

121550400400 is an abundant number, since it is smaller than the sum of its proper divisors (224054229488).

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

121550400400 is a wasteful number, since it uses less digits than its factorization.

121550400400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15690 (or 15679 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 22.

Adding to 121550400400 its reverse (4004055121), we get a palindrome (125554455521).

The spelling of 121550400400 in words is "one hundred twenty-one billion, five hundred fifty million, four hundred thousand, four hundred".