20724745551 has 8 divisors (see below), whose sum is σ = 28220930304. Its totient is φ = 13522528920.

The previous prime is 20724745537. The next prime is 20724745553. The reversal of 20724745551 is 15554742702.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20724745551 - 2⁹ = 20724745039 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20724745553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 73491865 + ... + 73492146.

It is an arithmetic number, because the mean of its divisors is an integer number (3527616288).

Almost surely, 2^20724745551 is an apocalyptic number.

20724745551 is a deficient number, since it is larger than the sum of its proper divisors (7496184753).

20724745551 is a wasteful number, since it uses less digits than its factorization.

20724745551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146984061.

The product of its (nonzero) digits is 392000, while the sum is 42.

The spelling of 20724745551 in words is "twenty billion, seven hundred twenty-four million, seven hundred forty-five thousand, five hundred fifty-one".