85561319551 has 2 divisors, whose sum is σ = 85561319552. Its totient is φ = 85561319550.

The previous prime is 85561319537. The next prime is 85561319561. The reversal of 85561319551 is 15591316558.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85561319551 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 85561319495 and 85561319504.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85561319561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42780659775 + 42780659776.

It is an arithmetic number, because the mean of its divisors is an integer number (42780659776).

Almost surely, 2^85561319551 is an apocalyptic number.

85561319551 is a deficient number, since it is larger than the sum of its proper divisors (1).

85561319551 is an equidigital number, since it uses as much as digits as its factorization.

85561319551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 810000, while the sum is 49.

The spelling of 85561319551 in words is "eighty-five billion, five hundred sixty-one million, three hundred nineteen thousand, five hundred fifty-one".