1861723013 has 2 divisors, whose sum is σ = 1861723014. Its totient is φ = 1861723012.

The previous prime is 1861722991. The next prime is 1861723079. The reversal of 1861723013 is 3103271681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1105363009 + 756360004 = 33247^2 + 27502^2 .

It is a cyclic number.

It is not a de Polignac number, because 1861723013 - 2¹⁰ = 1861721989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1861720013) 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, 930861506 + 930861507.

It is an arithmetic number, because the mean of its divisors is an integer number (930861507).

Almost surely, 2^1861723013 is an apocalyptic number.

It is an amenable number.

1861723013 is a deficient number, since it is larger than the sum of its proper divisors (1).

1861723013 is an equidigital number, since it uses as much as digits as its factorization.

1861723013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 1861723013 is about 43147.6883853585. The cubic root of 1861723013 is about 1230.1885742120.

Adding to 1861723013 its reverse (3103271681), we get a palindrome (4964994694).

The spelling of 1861723013 in words is "one billion, eight hundred sixty-one million, seven hundred twenty-three thousand, thirteen".