1656481729 has 4 divisors (see below), whose sum is σ = 1893121984. Its totient is φ = 1419841476.

The previous prime is 1656481727. The next prime is 1656481777. The reversal of 1656481729 is 9271846561.

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 1656481729 - 2¹ = 1656481727 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1656481721) 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, 118320117 + ... + 118320130.

It is an arithmetic number, because the mean of its divisors is an integer number (473280496).

Almost surely, 2^1656481729 is an apocalyptic number.

It is an amenable number.

1656481729 is a deficient number, since it is larger than the sum of its proper divisors (236640255).

1656481729 is an equidigital number, since it uses as much as digits as its factorization.

1656481729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236640254.

The product of its digits is 725760, while the sum is 49.

The square root of 1656481729 is about 40699.8983905366. The cubic root of 1656481729 is about 1183.2110493929.

The spelling of 1656481729 in words is "one billion, six hundred fifty-six million, four hundred eighty-one thousand, seven hundred twenty-nine".