20120321122421 has 4 divisors (see below), whose sum is σ = 21668038131852. Its totient is φ = 18572604112992.

The previous prime is 20120321122403. The next prime is 20120321122483. The reversal of 20120321122421 is 12422112302102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11656003699921 + 8464317422500 = 3414089^2 + 2909350^2 .

It is a cyclic number.

It is not a de Polignac number, because 20120321122421 - 2⁴² = 15722274611317 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 (20120321122021) 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, 773858504696 + ... + 773858504721.

It is an arithmetic number, because the mean of its divisors is an integer number (5417009532963).

Almost surely, 2^{20120321122421} is an apocalyptic number.

It is an amenable number.

20120321122421 is a deficient number, since it is larger than the sum of its proper divisors (1547717009431).

20120321122421 is a wasteful number, since it uses less digits than its factorization.

20120321122421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1547717009430.

The product of its (nonzero) digits is 768, while the sum is 23.

Adding to 20120321122421 its reverse (12422112302102), we get a palindrome (32542433424523).

The spelling of 20120321122421 in words is "twenty trillion, one hundred twenty billion, three hundred twenty-one million, one hundred twenty-two thousand, four hundred twenty-one".