121532400 has 450 divisors, whose sum is σ = 494891936. Its totient is φ = 28512000.

The previous prime is 121532399. The next prime is 121532401. The reversal of 121532400 is 4235121.

It is an interprime number because it is at equal distance from previous prime (121532399) and next prime (121532401).

It is a tau number, because it is divible by the number of its divisors (450).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121532401) by changing a digit.

It is a polite number, since it can be written in 89 ways as a sum of consecutive naturals, for example, 3920385 + ... + 3920415.

Almost surely, 2^121532400 is an apocalyptic number.

121532400 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 121532400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (247445968).

121532400 is an abundant number, since it is smaller than the sum of its proper divisors (373359536).

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

121532400 is a wasteful number, since it uses less digits than its factorization.

121532400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83 (or 52 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 121532400 is about 11024.1734384034. The cubic root of 121532400 is about 495.3331091180. Note that the first 3 decimals are identical.

Adding to 121532400 its reverse (4235121), we get a palindrome (125767521).

The spelling of 121532400 in words is "one hundred twenty-one million, five hundred thirty-two thousand, four hundred".