20732739 has 4 divisors (see below), whose sum is σ = 27643656. Its totient is φ = 13821824.

The previous prime is 20732737. The next prime is 20732759. The reversal of 20732739 is 93723702.

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 20732739 - 2¹ = 20732737 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20732737) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3455454 + ... + 3455459.

It is an arithmetic number, because the mean of its divisors is an integer number (6910914).

Almost surely, 2^20732739 is an apocalyptic number.

20732739 is a deficient number, since it is larger than the sum of its proper divisors (6910917).

20732739 is an equidigital number, since it uses as much as digits as its factorization.

20732739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6910916.

The product of its (nonzero) digits is 15876, while the sum is 33.

The square root of 20732739 is about 4553.3217544997. The cubic root of 20732739 is about 274.7170157867.

The spelling of 20732739 in words is "twenty million, seven hundred thirty-two thousand, seven hundred thirty-nine".