2181357716 has 6 divisors (see below), whose sum is σ = 3817376010. Its totient is φ = 1090678856.

The previous prime is 2181357713. The next prime is 2181357767. The reversal of 2181357716 is 6177531812.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 2171932816 + 9424900 = 46604^2 + 3070^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2181357713) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 272669711 + ... + 272669718.

It is an arithmetic number, because the mean of its divisors is an integer number (636229335).

Almost surely, 2^2181357716 is an apocalyptic number.

It is an amenable number.

2181357716 is a deficient number, since it is larger than the sum of its proper divisors (1636018294).

2181357716 is a wasteful number, since it uses less digits than its factorization.

2181357716 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 545339433 (or 545339431 counting only the distinct ones).

The product of its digits is 70560, while the sum is 41.

The square root of 2181357716 is about 46705.0073974943. The cubic root of 2181357716 is about 1296.9073855916.

The spelling of 2181357716 in words is "two billion, one hundred eighty-one million, three hundred fifty-seven thousand, seven hundred sixteen".