21307823461 has 4 divisors (see below), whose sum is σ = 22234250592. Its totient is φ = 20381396332.

The previous prime is 21307823431. The next prime is 21307823503. The reversal of 21307823461 is 16432870312.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21307823461 - 2¹¹ = 21307821413 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 21307823461.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21307823401) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 463213531 + ... + 463213576.

It is an arithmetic number, because the mean of its divisors is an integer number (5558562648).

Almost surely, 2^21307823461 is an apocalyptic number.

It is an amenable number.

21307823461 is a deficient number, since it is larger than the sum of its proper divisors (926427131).

21307823461 is an equidigital number, since it uses as much as digits as its factorization.

21307823461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 926427130.

The product of its (nonzero) digits is 48384, while the sum is 37.

The spelling of 21307823461 in words is "twenty-one billion, three hundred seven million, eight hundred twenty-three thousand, four hundred sixty-one".