6900531661 has 2 divisors, whose sum is σ = 6900531662.
Its totient is φ = 6900531660.
The previous prime is 6900531641. The next prime is 6900531697. The reversal of 6900531661 is 1661350096.
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 6900458761 + 72900 = 83069^2 + 270^2
It is a cyclic number.
It is not a de Polignac number, because 6900531661 - 223 = 6892143053 is a prime.
It is a self number, because there is not a number n which added to its sum of digits gives 6900531661.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (6900531601) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3450265830 + 3450265831.
It is an arithmetic number, because the mean of its divisors is an integer number (3450265831).
Almost surely, 26900531661 is an apocalyptic number.
It is an amenable number.
6900531661 is a deficient number, since it is larger than the sum of its proper divisors (1).
6900531661 is an equidigital number, since it uses as much as digits as its factorization.
6900531661 is an evil number, because the sum of its binary digits is even.
The product of its (nonzero) digits is 29160, while the sum is 37.
The square root of 6900531661 is about 83069.4387906888.
The cubic root of 6900531661 is about 1903.8271575507.
The spelling of 6900531661 in words is "six billion, nine hundred million, five hundred thirty-one thousand, six hundred sixty-one".