20513478 has 8 divisors (see below), whose sum is σ = 41026968. Its totient is φ = 6837824.

The previous prime is 20513461. The next prime is 20513513. The reversal of 20513478 is 87431502.

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

20513478 is an admirable number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1709451 + ... + 1709462.

It is an arithmetic number, because the mean of its divisors is an integer number (5128371).

Almost surely, 2^20513478 is an apocalyptic number.

20513478 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

20513478 is a wasteful number, since it uses less digits than its factorization.

20513478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3418918.

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 20513478 is about 4529.1807206160. The cubic root of 20513478 is about 273.7451499318.

The spelling of 20513478 in words is "twenty million, five hundred thirteen thousand, four hundred seventy-eight".