20681478 has 12 divisors (see below), whose sum is σ = 44809908. Its totient is φ = 6893820.

The previous prime is 20681477. The next prime is 20681491. The reversal of 20681478 is 87418602.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

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 polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 574468 + ... + 574503.

It is an arithmetic number, because the mean of its divisors is an integer number (3734159).

Almost surely, 2^20681478 is an apocalyptic number.

20681478 is an abundant number, since it is smaller than the sum of its proper divisors (24128430).

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

20681478 is a wasteful number, since it uses less digits than its factorization.

20681478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1148979 (or 1148976 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 20681478 is about 4547.6893033715. The cubic root of 20681478 is about 274.4904194054.

The spelling of 20681478 in words is "twenty million, six hundred eighty-one thousand, four hundred seventy-eight".