56661739 has 4 divisors (see below), whose sum is σ = 56677680. Its totient is φ = 56645800.

The previous prime is 56661727. The next prime is 56661749. The reversal of 56661739 is 93716665.

56661739 is nontrivially palindromic in base 15.

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 56661739 - 2¹³ = 56653547 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 56661695 and 56661704.

It is not an unprimeable number, because it can be changed into a prime (56661749) 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, 57 + ... + 10645.

It is an arithmetic number, because the mean of its divisors is an integer number (14169420).

Almost surely, 2^56661739 is an apocalyptic number.

56661739 is a deficient number, since it is larger than the sum of its proper divisors (15941).

56661739 is a wasteful number, since it uses less digits than its factorization.

56661739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15940.

The product of its digits is 204120, while the sum is 43.

The square root of 56661739 is about 7527.3992188537. The cubic root of 56661739 is about 384.0873169312.

The spelling of 56661739 in words is "fifty-six million, six hundred sixty-one thousand, seven hundred thirty-nine".