20479919 has 2 divisors, whose sum is σ = 20479920. Its totient is φ = 20479918.

The previous prime is 20479909. The next prime is 20479937. The reversal of 20479919 is 91997402.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20479919 is a prime.

It is a super-2 number, since 2×20479919² = 838854164493122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20479909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10239959 + 10239960.

It is an arithmetic number, because the mean of its divisors is an integer number (10239960).

Almost surely, 2^20479919 is an apocalyptic number.

20479919 is a deficient number, since it is larger than the sum of its proper divisors (1).

20479919 is an equidigital number, since it uses as much as digits as its factorization.

20479919 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 41.

The square root of 20479919 is about 4525.4744502649. The cubic root of 20479919 is about 273.5957907697.

The spelling of 20479919 in words is "twenty million, four hundred seventy-nine thousand, nine hundred nineteen".