21615601011123 has 16 divisors (see below), whose sum is σ = 33020198493696. Its totient is φ = 12320969577600.

The previous prime is 21615601011107. The next prime is 21615601011131. The reversal of 21615601011123 is 32111010651612.

It is not a de Polignac number, because 21615601011123 - 2⁴ = 21615601011107 is a prime.

It is a super-2 number, since 2×21615601011123² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21615601011023) 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, 1283425911 + ... + 1283442752.

It is an arithmetic number, because the mean of its divisors is an integer number (2063762405856).

Almost surely, 2^{21615601011123} is an apocalyptic number.

21615601011123 is a deficient number, since it is larger than the sum of its proper divisors (11404597482573).

21615601011123 is a wasteful number, since it uses less digits than its factorization.

21615601011123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2566869074.

The product of its (nonzero) digits is 2160, while the sum is 30.

Adding to 21615601011123 its reverse (32111010651612), we get a palindrome (53726611662735).

The spelling of 21615601011123 in words is "twenty-one trillion, six hundred fifteen billion, six hundred one million, eleven thousand, one hundred twenty-three".