121425521 has 4 divisors (see below), whose sum is σ = 138772032. Its totient is φ = 104079012.

The previous prime is 121425511. The next prime is 121425539. The reversal of 121425521 is 125524121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 121425521 - 2⁶ = 121425457 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121425511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8673245 + ... + 8673258.

It is an arithmetic number, because the mean of its divisors is an integer number (34693008).

Almost surely, 2^121425521 is an apocalyptic number.

It is an amenable number.

121425521 is a deficient number, since it is larger than the sum of its proper divisors (17346511).

121425521 is an equidigital number, since it uses as much as digits as its factorization.

121425521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17346510.

The product of its digits is 800, while the sum is 23.

The square root of 121425521 is about 11019.3248885764. The cubic root of 121425521 is about 495.1878632573.

Adding to 121425521 its reverse (125524121), we get a palindrome (246949642).

The spelling of 121425521 in words is "one hundred twenty-one million, four hundred twenty-five thousand, five hundred twenty-one".