21976069 has 2 divisors, whose sum is σ = 21976070. Its totient is φ = 21976068.

The previous prime is 21976057. The next prime is 21976081. The reversal of 21976069 is 96067912.

It is a balanced prime because it is at equal distance from previous prime (21976057) and next prime (21976081).

It can be written as a sum of positive squares in only one way, i.e., 21967969 + 8100 = 4687^2 + 90^2 .

It is a cyclic number.

It is not a de Polignac number, because 21976069 - 2⁵ = 21976037 is a prime.

It is a super-2 number, since 2×21976069² = 965895217385522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21976169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10988034 + 10988035.

It is an arithmetic number, because the mean of its divisors is an integer number (10988035).

Almost surely, 2^21976069 is an apocalyptic number.

It is an amenable number.

21976069 is a deficient number, since it is larger than the sum of its proper divisors (1).

21976069 is an equidigital number, since it uses as much as digits as its factorization.

21976069 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40824, while the sum is 40.

The square root of 21976069 is about 4687.8640125328. The cubic root of 21976069 is about 280.1022968054.

The spelling of 21976069 in words is "twenty-one million, nine hundred seventy-six thousand, sixty-nine".