20578740 has 96 divisors (see below), whose sum is σ = 70936320. Its totient is φ = 4340736.

The previous prime is 20578717. The next prime is 20578741. The reversal of 20578740 is 4787502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20578741) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3576 + ... + 7344.

It is an arithmetic number, because the mean of its divisors is an integer number (738920).

Almost surely, 2^20578740 is an apocalyptic number.

20578740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20578740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35468160).

20578740 is an abundant number, since it is smaller than the sum of its proper divisors (50357580).

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

20578740 is a wasteful number, since it uses less digits than its factorization.

20578740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3801 (or 3799 counting only the distinct ones).

The product of its (nonzero) digits is 15680, while the sum is 33.

The square root of 20578740 is about 4536.3796137449. The cubic root of 20578740 is about 274.0351420996.

The spelling of 20578740 in words is "twenty million, five hundred seventy-eight thousand, seven hundred forty".