249749660161 has 2 divisors, whose sum is σ = 249749660162. Its totient is φ = 249749660160.

The previous prime is 249749660113. The next prime is 249749660197. The reversal of 249749660161 is 161066947942.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 249681101761 + 68558400 = 499681^2 + 8280^2 .

It is a cyclic number.

It is not a de Polignac number, because 249749660161 - 2¹³ = 249749651969 is a prime.

It is not a weakly prime, because it can be changed into another prime (249749660261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 124874830080 + 124874830081.

It is an arithmetic number, because the mean of its divisors is an integer number (124874830081).

Almost surely, 2^249749660161 is an apocalyptic number.

It is an amenable number.

249749660161 is a deficient number, since it is larger than the sum of its proper divisors (1).

249749660161 is an equidigital number, since it uses as much as digits as its factorization.

249749660161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3919104, while the sum is 55.

The spelling of 249749660161 in words is "two hundred forty-nine billion, seven hundred forty-nine million, six hundred sixty thousand, one hundred sixty-one".