21051126520261 has 8 divisors (see below), whose sum is σ = 21062205102848. Its totient is φ = 21040049646000.

The previous prime is 21051126520199. The next prime is 21051126520301. The reversal of 21051126520261 is 16202562115012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21051126520261 - 2⁹ = 21051126519749 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 (21051126520661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24609931 + ... + 25450951.

It is an arithmetic number, because the mean of its divisors is an integer number (2632775637856).

Almost surely, 2^{21051126520261} is an apocalyptic number.

It is an amenable number.

21051126520261 is a deficient number, since it is larger than the sum of its proper divisors (11078582587).

21051126520261 is a wasteful number, since it uses less digits than its factorization.

21051126520261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 854163.

The product of its (nonzero) digits is 14400, while the sum is 34.

Adding to 21051126520261 its reverse (16202562115012), we get a palindrome (37253688635273).

The spelling of 21051126520261 in words is "twenty-one trillion, fifty-one billion, one hundred twenty-six million, five hundred twenty thousand, two hundred sixty-one".