21961246793 has 2 divisors, whose sum is σ = 21961246794. Its totient is φ = 21961246792.

The previous prime is 21961246771. The next prime is 21961246823. The reversal of 21961246793 is 39764216912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21912288784 + 48958009 = 148028^2 + 6997^2 .

It is a cyclic number.

It is not a de Polignac number, because 21961246793 - 2¹⁰ = 21961245769 is a prime.

It is not a weakly prime, because it can be changed into another prime (21961246753) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10980623396 + 10980623397.

It is an arithmetic number, because the mean of its divisors is an integer number (10980623397).

Almost surely, 2^21961246793 is an apocalyptic number.

It is an amenable number.

21961246793 is a deficient number, since it is larger than the sum of its proper divisors (1).

21961246793 is an equidigital number, since it uses as much as digits as its factorization.

21961246793 is an evil number, because the sum of its binary digits is even.

The product of its digits is 979776, while the sum is 50.

The spelling of 21961246793 in words is "twenty-one billion, nine hundred sixty-one million, two hundred forty-six thousand, seven hundred ninety-three".