20742520 has 32 divisors (see below), whose sum is σ = 46947600. Its totient is φ = 8247808.

The previous prime is 20742517. The next prime is 20742521. The reversal of 20742520 is 2524702.

It is a junction number, because it is equal to n+sod(n) for n = 20742491 and 20742500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20742521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5712 + ... + 8608.

Almost surely, 2^20742520 is an apocalyptic number.

20742520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20742520 is an abundant number, since it is smaller than the sum of its proper divisors (26205080).

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

20742520 is a wasteful number, since it uses less digits than its factorization.

20742520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3087 (or 3083 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 22.

The square root of 20742520 is about 4554.3956789019. The cubic root of 20742520 is about 274.7602097049.

The spelling of 20742520 in words is "twenty million, seven hundred forty-two thousand, five hundred twenty".