11172761257661 has 2 divisors, whose sum is σ = 11172761257662. Its totient is φ = 11172761257660.

The previous prime is 11172761257643. The next prime is 11172761257673. The reversal of 11172761257661 is 16675216727111.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7244139952036 + 3928621305625 = 2691494^2 + 1982075^2 .

It is a cyclic number.

It is not a de Polignac number, because 11172761257661 - 2²² = 11172757063357 is a prime.

It is a super-2 number, since 2×11172761257661² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11172761257061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5586380628830 + 5586380628831.

It is an arithmetic number, because the mean of its divisors is an integer number (5586380628831).

Almost surely, 2^{11172761257661} is an apocalyptic number.

It is an amenable number.

11172761257661 is a deficient number, since it is larger than the sum of its proper divisors (1).

11172761257661 is an equidigital number, since it uses as much as digits as its factorization.

11172761257661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1481760, while the sum is 53.

The spelling of 11172761257661 in words is "eleven trillion, one hundred seventy-two billion, seven hundred sixty-one million, two hundred fifty-seven thousand, six hundred sixty-one".