16861155761 has 2 divisors, whose sum is σ = 16861155762. Its totient is φ = 16861155760.

The previous prime is 16861155737. The next prime is 16861155811. The reversal of 16861155761 is 16755116861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16047822400 + 813333361 = 126680^2 + 28519^2 .

It is a cyclic number.

It is not a de Polignac number, because 16861155761 - 2⁶ = 16861155697 is a prime.

It is not a weakly prime, because it can be changed into another prime (16861155361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8430577880 + 8430577881.

It is an arithmetic number, because the mean of its divisors is an integer number (8430577881).

Almost surely, 2^16861155761 is an apocalyptic number.

It is an amenable number.

16861155761 is a deficient number, since it is larger than the sum of its proper divisors (1).

16861155761 is an equidigital number, since it uses as much as digits as its factorization.

16861155761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 302400, while the sum is 47.

The spelling of 16861155761 in words is "sixteen billion, eight hundred sixty-one million, one hundred fifty-five thousand, seven hundred sixty-one".