21294835261 has 16 divisors (see below), whose sum is σ = 24937162624. Its totient is φ = 17803727424.

The previous prime is 21294835259. The next prime is 21294835277. The reversal of 21294835261 is 16253849212.

It is not a de Polignac number, because 21294835261 - 2¹ = 21294835259 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21294815261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 172375 + ... + 268891.

It is an arithmetic number, because the mean of its divisors is an integer number (1558572664).

Almost surely, 2^21294835261 is an apocalyptic number.

It is an amenable number.

21294835261 is a deficient number, since it is larger than the sum of its proper divisors (3642327363).

21294835261 is an equidigital number, since it uses as much as digits as its factorization.

21294835261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97300.

The product of its digits is 207360, while the sum is 43.

The spelling of 21294835261 in words is "twenty-one billion, two hundred ninety-four million, eight hundred thirty-five thousand, two hundred sixty-one".