21461010685 has 16 divisors (see below), whose sum is σ = 26437948992. Its totient is φ = 16714115200.

The previous prime is 21461010643. The next prime is 21461010689. The reversal of 21461010685 is 58601016412.

It is a de Polignac number, because none of the positive numbers 2^k-21461010685 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21461010685.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21461010689) 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, 16351 + ... + 207820.

It is an arithmetic number, because the mean of its divisors is an integer number (1652371812).

Almost surely, 2^21461010685 is an apocalyptic number.

It is an amenable number.

21461010685 is a deficient number, since it is larger than the sum of its proper divisors (4976938307).

21461010685 is a wasteful number, since it uses less digits than its factorization.

21461010685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224684.

The product of its (nonzero) digits is 11520, while the sum is 34.

The spelling of 21461010685 in words is "twenty-one billion, four hundred sixty-one million, ten thousand, six hundred eighty-five".