20724351 has 4 divisors (see below), whose sum is σ = 27632472. Its totient is φ = 13816232.

The previous prime is 20724349. The next prime is 20724359. The reversal of 20724351 is 15342702.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20724351 - 2¹ = 20724349 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20724359) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3454056 + ... + 3454061.

It is an arithmetic number, because the mean of its divisors is an integer number (6908118).

Almost surely, 2^20724351 is an apocalyptic number.

20724351 is a deficient number, since it is larger than the sum of its proper divisors (6908121).

20724351 is an equidigital number, since it uses as much as digits as its factorization.

20724351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6908120.

The product of its (nonzero) digits is 1680, while the sum is 24.

The square root of 20724351 is about 4552.4005755206. The cubic root of 20724351 is about 274.6799626802.

The spelling of 20724351 in words is "twenty million, seven hundred twenty-four thousand, three hundred fifty-one".