50001601111661 has 2 divisors, whose sum is σ = 50001601111662. Its totient is φ = 50001601111660.

The previous prime is 50001601111613. The next prime is 50001601111691. The reversal of 50001601111661 is 16611110610005.

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., 41045407675561 + 8956193436100 = 6406669^2 + 2992690^2 .

It is a cyclic number.

It is not a de Polignac number, because 50001601111661 - 2²² = 50001596917357 is a prime.

It is a super-2 number, since 2×50001601111661² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (50001601111691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25000800555830 + 25000800555831.

It is an arithmetic number, because the mean of its divisors is an integer number (25000800555831).

Almost surely, 2^{50001601111661} is an apocalyptic number.

It is an amenable number.

50001601111661 is a deficient number, since it is larger than the sum of its proper divisors (1).

50001601111661 is an equidigital number, since it uses as much as digits as its factorization.

50001601111661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080, while the sum is 29.

Adding to 50001601111661 its reverse (16611110610005), we get a palindrome (66612711721666).

The spelling of 50001601111661 in words is "fifty trillion, one billion, six hundred one million, one hundred eleven thousand, six hundred sixty-one".