21582775499 has 2 divisors, whose sum is σ = 21582775500. Its totient is φ = 21582775498.

The previous prime is 21582775481. The next prime is 21582775517. The reversal of 21582775499 is 99457728512.

It is a balanced prime because it is at equal distance from previous prime (21582775481) and next prime (21582775517).

It is a cyclic number.

It is not a de Polignac number, because 21582775499 - 2¹⁶ = 21582709963 is a prime.

It is not a weakly prime, because it can be changed into another prime (21582705499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10791387749 + 10791387750.

It is an arithmetic number, because the mean of its divisors is an integer number (10791387750).

Almost surely, 2^21582775499 is an apocalyptic number.

21582775499 is a deficient number, since it is larger than the sum of its proper divisors (1).

21582775499 is an equidigital number, since it uses as much as digits as its factorization.

21582775499 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12700800, while the sum is 59.

The spelling of 21582775499 in words is "twenty-one billion, five hundred eighty-two million, seven hundred seventy-five thousand, four hundred ninety-nine".