20906478 has 32 divisors (see below), whose sum is σ = 46725120. Its totient is φ = 6928920.

The previous prime is 20906461. The next prime is 20906489. The reversal of 20906478 is 87460902.

20906478 is a `hidden beast` number, since 2 + 0 + 9 + 0 + 647 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9301 + ... + 11327.

It is an arithmetic number, because the mean of its divisors is an integer number (1460160).

Almost surely, 2^20906478 is an apocalyptic number.

20906478 is an abundant number, since it is smaller than the sum of its proper divisors (25818642).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20906478 is a wasteful number, since it uses less digits than its factorization.

20906478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2229 (or 2223 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 20906478 is about 4572.3602220298. The cubic root of 20906478 is about 275.4822524286.

The spelling of 20906478 in words is "twenty million, nine hundred six thousand, four hundred seventy-eight".