61211539673 has 2 divisors, whose sum is σ = 61211539674. Its totient is φ = 61211539672.

The previous prime is 61211539637. The next prime is 61211539759. The reversal of 61211539673 is 37693511216.

Together with previous prime (61211539637) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 50092258969 + 11119280704 = 223813^2 + 105448^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61211539673 is a prime.

It is not a weakly prime, because it can be changed into another prime (61211539603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30605769836 + 30605769837.

It is an arithmetic number, because the mean of its divisors is an integer number (30605769837).

Almost surely, 2^61211539673 is an apocalyptic number.

It is an amenable number.

61211539673 is a deficient number, since it is larger than the sum of its proper divisors (1).

61211539673 is an equidigital number, since it uses as much as digits as its factorization.

61211539673 is an evil number, because the sum of its binary digits is even.

The product of its digits is 204120, while the sum is 44.

The spelling of 61211539673 in words is "sixty-one billion, two hundred eleven million, five hundred thirty-nine thousand, six hundred seventy-three".