121551442013 has 4 divisors (see below), whose sum is σ = 122096515968. Its totient is φ = 121006368060.

The previous prime is 121551441941. The next prime is 121551442021. The reversal of 121551442013 is 310244155121.

It is a happy number.

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 121551442013 - 2²⁸ = 121283006557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121551447013) 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, 272536643 + ... + 272537088.

It is an arithmetic number, because the mean of its divisors is an integer number (30524128992).

Almost surely, 2^121551442013 is an apocalyptic number.

It is an amenable number.

121551442013 is a deficient number, since it is larger than the sum of its proper divisors (545073955).

121551442013 is an equidigital number, since it uses as much as digits as its factorization.

121551442013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 545073954.

The product of its (nonzero) digits is 4800, while the sum is 29.

Adding to 121551442013 its reverse (310244155121), we get a palindrome (431795597134).

The spelling of 121551442013 in words is "one hundred twenty-one billion, five hundred fifty-one million, four hundred forty-two thousand, thirteen".