1772426137661 has 2 divisors, whose sum is σ = 1772426137662. Its totient is φ = 1772426137660.

The previous prime is 1772426137639. The next prime is 1772426137679. The reversal of 1772426137661 is 1667316242771.

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., 1415312329561 + 357113808100 = 1189669^2 + 597590^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1772426137661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1772426137681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 886213068830 + 886213068831.

It is an arithmetic number, because the mean of its divisors is an integer number (886213068831).

Almost surely, 2^{1772426137661} is an apocalyptic number.

It is an amenable number.

1772426137661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1772426137661 is an equidigital number, since it uses as much as digits as its factorization.

1772426137661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3556224, while the sum is 53.

The spelling of 1772426137661 in words is "one trillion, seven hundred seventy-two billion, four hundred twenty-six million, one hundred thirty-seven thousand, six hundred sixty-one".