21369049679 has 2 divisors, whose sum is σ = 21369049680. Its totient is φ = 21369049678.

The previous prime is 21369049651. The next prime is 21369049699. The reversal of 21369049679 is 97694096312.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21369049679 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21369049619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10684524839 + 10684524840.

It is an arithmetic number, because the mean of its divisors is an integer number (10684524840).

Almost surely, 2^21369049679 is an apocalyptic number.

21369049679 is a deficient number, since it is larger than the sum of its proper divisors (1).

21369049679 is an equidigital number, since it uses as much as digits as its factorization.

21369049679 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4408992, while the sum is 56.

The spelling of 21369049679 in words is "twenty-one billion, three hundred sixty-nine million, forty-nine thousand, six hundred seventy-nine".