20481729 has 4 divisors (see below), whose sum is σ = 27308976. Its totient is φ = 13654484.

The previous prime is 20481709. The next prime is 20481733. The reversal of 20481729 is 92718402.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20481729 - 2⁹ = 20481217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20481729.

It is not an unprimeable number, because it can be changed into a prime (20481709) 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, 3413619 + ... + 3413624.

It is an arithmetic number, because the mean of its divisors is an integer number (6827244).

Almost surely, 2^20481729 is an apocalyptic number.

It is an amenable number.

20481729 is a deficient number, since it is larger than the sum of its proper divisors (6827247).

20481729 is an equidigital number, since it uses as much as digits as its factorization.

20481729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6827246.

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 20481729 is about 4525.6744248786. The cubic root of 20481729 is about 273.6038505964.

The spelling of 20481729 in words is "twenty million, four hundred eighty-one thousand, seven hundred twenty-nine".