6542253661 has 2 divisors, whose sum is σ = 6542253662. Its totient is φ = 6542253660.

The previous prime is 6542253631. The next prime is 6542253673. The reversal of 6542253661 is 1663522456.

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., 5765516761 + 776736900 = 75931^2 + 27870^2 .

It is a cyclic number.

It is not a de Polignac number, because 6542253661 - 2¹⁷ = 6542122589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6542253631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3271126830 + 3271126831.

It is an arithmetic number, because the mean of its divisors is an integer number (3271126831).

Almost surely, 2^6542253661 is an apocalyptic number.

It is an amenable number.

6542253661 is a deficient number, since it is larger than the sum of its proper divisors (1).

6542253661 is an equidigital number, since it uses as much as digits as its factorization.

6542253661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 259200, while the sum is 40.

The square root of 6542253661 is about 80884.1990811555. The cubic root of 6542253661 is about 1870.2907514967.

The spelling of 6542253661 in words is "six billion, five hundred forty-two million, two hundred fifty-three thousand, six hundred sixty-one".