21504652126261 has 8 divisors (see below), whose sum is σ = 22637839322880. Its totient is φ = 20371601269728.

The previous prime is 21504652126231. The next prime is 21504652126267. The reversal of 21504652126261 is 16262125640512.

It is a happy number.

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

It is not a de Polignac number, because 21504652126261 - 2¹⁵ = 21504652093493 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21504652126267) 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, 33761176 + ... + 34392241.

It is an arithmetic number, because the mean of its divisors is an integer number (2829729915360).

Almost surely, 2^{21504652126261} is an apocalyptic number.

It is an amenable number.

21504652126261 is a deficient number, since it is larger than the sum of its proper divisors (1133187196619).

21504652126261 is a wasteful number, since it uses less digits than its factorization.

21504652126261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68170043.

The product of its (nonzero) digits is 345600, while the sum is 43.

Adding to 21504652126261 its reverse (16262125640512), we get a palindrome (37766777766773).

The spelling of 21504652126261 in words is "twenty-one trillion, five hundred four billion, six hundred fifty-two million, one hundred twenty-six thousand, two hundred sixty-one".