20518542 has 32 divisors (see below), whose sum is σ = 49743360. Its totient is φ = 6217560.

The previous prime is 20518529. The next prime is 20518577. The reversal of 20518542 is 24581502.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

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, 16678 + ... + 17865.

It is an arithmetic number, because the mean of its divisors is an integer number (1554480).

Almost surely, 2^20518542 is an apocalyptic number.

20518542 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

20518542 is an abundant number, since it is smaller than the sum of its proper divisors (29224818).

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

20518542 is a wasteful number, since it uses less digits than its factorization.

20518542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34565 (or 34559 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 27.

The square root of 20518542 is about 4529.7397276223. The cubic root of 20518542 is about 273.7676738448.

The spelling of 20518542 in words is "twenty million, five hundred eighteen thousand, five hundred forty-two".