121421440 has 64 divisors (see below), whose sum is σ = 331752960. Its totient is φ = 41628672.

The previous prime is 121421423. The next prime is 121421453. The reversal of 121421440 is 44124121.

It is a tau number, because it is divible by the number of its divisors (64).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9072 + ... + 18031.

It is an arithmetic number, because the mean of its divisors is an integer number (5183640).

Almost surely, 2^121421440 is an apocalyptic number.

121421440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121421440 is an abundant number, since it is smaller than the sum of its proper divisors (210331520).

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

121421440 is an equidigital number, since it uses as much as digits as its factorization.

121421440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27129 (or 27117 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 121421440 is about 11019.1397123369. The cubic root of 121421440 is about 495.1823155924.

Adding to 121421440 its reverse (44124121), we get a palindrome (165545561).

The spelling of 121421440 in words is "one hundred twenty-one million, four hundred twenty-one thousand, four hundred forty".