21677940499 has 2 divisors, whose sum is σ = 21677940500. Its totient is φ = 21677940498.

The previous prime is 21677940469. The next prime is 21677940533. The reversal of 21677940499 is 99404977612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21677940499 - 2¹³ = 21677932307 is a prime.

It is not a weakly prime, because it can be changed into another prime (21677940419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10838970249 + 10838970250.

It is an arithmetic number, because the mean of its divisors is an integer number (10838970250).

Almost surely, 2^21677940499 is an apocalyptic number.

21677940499 is a deficient number, since it is larger than the sum of its proper divisors (1).

21677940499 is an equidigital number, since it uses as much as digits as its factorization.

21677940499 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6858432, while the sum is 58.

The spelling of 21677940499 in words is "twenty-one billion, six hundred seventy-seven million, nine hundred forty thousand, four hundred ninety-nine".