21123101441021 has 16 divisors (see below), whose sum is σ = 22342366824960. Its totient is φ = 19929409568640.

The previous prime is 21123101441009. The next prime is 21123101441023. The reversal of 21123101441021 is 12014410132112.

It is a cyclic number.

It is not a de Polignac number, because 21123101441021 - 2¹⁰ = 21123101439997 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21123101441023) 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, 3837920 + ... + 7548233.

It is an arithmetic number, because the mean of its divisors is an integer number (1396397926560).

Almost surely, 2^{21123101441021} is an apocalyptic number.

It is an amenable number.

21123101441021 is a deficient number, since it is larger than the sum of its proper divisors (1219265383939).

21123101441021 is a wasteful number, since it uses less digits than its factorization.

21123101441021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11387276.

The product of its (nonzero) digits is 384, while the sum is 23.

Adding to 21123101441021 its reverse (12014410132112), we get a palindrome (33137511573133).

The spelling of 21123101441021 in words is "twenty-one trillion, one hundred twenty-three billion, one hundred one million, four hundred forty-one thousand, twenty-one".