55713821 has 2 divisors, whose sum is σ = 55713822. Its totient is φ = 55713820.

The previous prime is 55713809. The next prime is 55713839. The reversal of 55713821 is 12831755.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 33988900 + 21724921 = 5830^2 + 4661^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55713821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55713221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27856910 + 27856911.

It is an arithmetic number, because the mean of its divisors is an integer number (27856911).

Almost surely, 2^55713821 is an apocalyptic number.

It is an amenable number.

55713821 is a deficient number, since it is larger than the sum of its proper divisors (1).

55713821 is an equidigital number, since it uses as much as digits as its factorization.

55713821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8400, while the sum is 32.

The square root of 55713821 is about 7464.1691433139. The cubic root of 55713821 is about 381.9334080717.

The spelling of 55713821 in words is "fifty-five million, seven hundred thirteen thousand, eight hundred twenty-one".