21680059 has 2 divisors, whose sum is σ = 21680060. Its totient is φ = 21680058.

The previous prime is 21680027. The next prime is 21680069. The reversal of 21680059 is 95008612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21680059 - 2⁵ = 21680027 is a prime.

It is a super-3 number, since 3×21680059³ (a number of 23 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21680059.

It is not a weakly prime, because it can be changed into another prime (21680069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10840029 + 10840030.

It is an arithmetic number, because the mean of its divisors is an integer number (10840030).

Almost surely, 2^21680059 is an apocalyptic number.

21680059 is a deficient number, since it is larger than the sum of its proper divisors (1).

21680059 is an equidigital number, since it uses as much as digits as its factorization.

21680059 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 31.

The square root of 21680059 is about 4656.1850263923. The cubic root of 21680059 is about 278.8389807561.

The spelling of 21680059 in words is "twenty-one million, six hundred eighty thousand, fifty-nine".