612099721861 has 2 divisors, whose sum is σ = 612099721862. Its totient is φ = 612099721860.

The previous prime is 612099721843. The next prime is 612099721897. The reversal of 612099721861 is 168127990216.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 611671024836 + 428697025 = 782094^2 + 20705^2 .

It is a cyclic number.

It is not a de Polignac number, because 612099721861 - 2²³ = 612091333253 is a prime.

It is a super-2 number, since 2×612099721861² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 612099721799 and 612099721808.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (612099721661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 306049860930 + 306049860931.

It is an arithmetic number, because the mean of its divisors is an integer number (306049860931).

Almost surely, 2^612099721861 is an apocalyptic number.

It is an amenable number.

612099721861 is a deficient number, since it is larger than the sum of its proper divisors (1).

612099721861 is an equidigital number, since it uses as much as digits as its factorization.

612099721861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 653184, while the sum is 52.

The spelling of 612099721861 in words is "six hundred twelve billion, ninety-nine million, seven hundred twenty-one thousand, eight hundred sixty-one".