20681479 has 12 divisors (see below), whose sum is σ = 25909464. Its totient is φ = 16362864.

The previous prime is 20681477. The next prime is 20681491. The reversal of 20681479 is 97418602.

It is not a de Polignac number, because 20681479 - 2¹ = 20681477 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20681471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15597 + ... + 16870.

It is an arithmetic number, because the mean of its divisors is an integer number (2159122).

Almost surely, 2^20681479 is an apocalyptic number.

20681479 is a deficient number, since it is larger than the sum of its proper divisors (5227985).

20681479 is a wasteful number, since it uses less digits than its factorization.

20681479 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32494 (or 32487 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 20681479 is about 4547.6894133175. The cubic root of 20681479 is about 274.4904238295.

The spelling of 20681479 in words is "twenty million, six hundred eighty-one thousand, four hundred seventy-nine".