20535720 has 32 divisors (see below), whose sum is σ = 61607520. Its totient is φ = 5476160.

The previous prime is 20535719. The next prime is 20535731. The reversal of 20535720 is 2753502.

It is a hoax number, since the sum of its digits (24) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 85446 + ... + 85685.

It is an arithmetic number, because the mean of its divisors is an integer number (1925235).

Almost surely, 2^20535720 is an apocalyptic number.

20535720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20535720 is an abundant number, since it is smaller than the sum of its proper divisors (41071800).

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

20535720 is a wasteful number, since it uses less digits than its factorization.

20535720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171145 (or 171141 counting only the distinct ones).

The product of its (nonzero) digits is 2100, while the sum is 24.

The square root of 20535720 is about 4531.6354663631. The cubic root of 20535720 is about 273.8440514181.

The spelling of 20535720 in words is "twenty million, five hundred thirty-five thousand, seven hundred twenty".