21260455064121 has 32 divisors (see below), whose sum is σ = 34889260105728. Its totient is φ = 11214206902080.

The previous prime is 21260455064119. The next prime is 21260455064137. The reversal of 21260455064121 is 12146055406212.

It is not a de Polignac number, because 21260455064121 - 2¹ = 21260455064119 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a self number, because there is not a number n which added to its sum of digits gives 21260455064121.

It is not an unprimeable number, because it can be changed into a prime (21260455064221) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 38731240 + ... + 39276326.

It is an arithmetic number, because the mean of its divisors is an integer number (1090289378304).

Almost surely, 2^{21260455064121} is an apocalyptic number.

21260455064121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21260455064121 is a deficient number, since it is larger than the sum of its proper divisors (13628805041607).

21260455064121 is a wasteful number, since it uses less digits than its factorization.

21260455064121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 687981.

The product of its (nonzero) digits is 115200, while the sum is 39.

The spelling of 21260455064121 in words is "twenty-one trillion, two hundred sixty billion, four hundred fifty-five million, sixty-four thousand, one hundred twenty-one".