21679033 has 2 divisors, whose sum is σ = 21679034. Its totient is φ = 21679032.

The previous prime is 21679001. The next prime is 21679039. The reversal of 21679033 is 33097612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14645929 + 7033104 = 3827^2 + 2652^2 .

It is a cyclic number.

It is not a de Polignac number, because 21679033 - 2⁵ = 21679001 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21678986 and 21679004.

It is not a weakly prime, because it can be changed into another prime (21679039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10839516 + 10839517.

It is an arithmetic number, because the mean of its divisors is an integer number (10839517).

Almost surely, 2^21679033 is an apocalyptic number.

It is an amenable number.

21679033 is a deficient number, since it is larger than the sum of its proper divisors (1).

21679033 is an equidigital number, since it uses as much as digits as its factorization.

21679033 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6804, while the sum is 31.

The square root of 21679033 is about 4656.0748490547. The cubic root of 21679033 is about 278.8345820395.

The spelling of 21679033 in words is "twenty-one million, six hundred seventy-nine thousand, thirty-three".