21121023420413 has 16 divisors (see below), whose sum is σ = 24727430359296. Its totient is φ = 17661909471360.

The previous prime is 21121023420403. The next prime is 21121023420487. The reversal of 21121023420413 is 31402432012112.

It is a happy number.

It is not a de Polignac number, because 21121023420413 - 2⁸ = 21121023420157 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121023420403) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19453295 + ... + 20510307.

It is an arithmetic number, because the mean of its divisors is an integer number (1545464397456).

Almost surely, 2^{21121023420413} is an apocalyptic number.

It is an amenable number.

21121023420413 is a deficient number, since it is larger than the sum of its proper divisors (3606406938883).

21121023420413 is a wasteful number, since it uses less digits than its factorization.

21121023420413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1126684.

The product of its (nonzero) digits is 2304, while the sum is 26.

Adding to 21121023420413 its reverse (31402432012112), we get a palindrome (52523455432525).

The spelling of 21121023420413 in words is "twenty-one trillion, one hundred twenty-one billion, twenty-three million, four hundred twenty thousand, four hundred thirteen".