20879247 has 8 divisors (see below), whose sum is σ = 29476656. Its totient is φ = 13100672.

The previous prime is 20879227. The next prime is 20879251. The reversal of 20879247 is 74297802.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20879247 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20879227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 204648 + ... + 204749.

It is an arithmetic number, because the mean of its divisors is an integer number (3684582).

Almost surely, 2^20879247 is an apocalyptic number.

20879247 is a deficient number, since it is larger than the sum of its proper divisors (8597409).

20879247 is a wasteful number, since it uses less digits than its factorization.

20879247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409417.

The product of its (nonzero) digits is 56448, while the sum is 39.

The square root of 20879247 is about 4569.3814679889. The cubic root of 20879247 is about 275.3625938777.

The spelling of 20879247 in words is "twenty million, eight hundred seventy-nine thousand, two hundred forty-seven".