77642491825 has 12 divisors (see below), whose sum is σ = 98878763740. Its totient is φ = 60435236160.

The previous prime is 77642491811. The next prime is 77642491831. The reversal of 77642491825 is 52819424677.

It can be written as a sum of positive squares in 6 ways, for example, as 1686580624 + 75955911201 = 41068^2 + 275601^2 .

It is not a de Polignac number, because 77642491825 - 2¹⁷ = 77642360753 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 41967990 + ... + 41969839.

Almost surely, 2^77642491825 is an apocalyptic number.

It is an amenable number.

77642491825 is a deficient number, since it is larger than the sum of its proper divisors (21236271915).

77642491825 is a wasteful number, since it uses less digits than its factorization.

77642491825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83937876 (or 83937871 counting only the distinct ones).

The product of its digits is 6773760, while the sum is 55.

The spelling of 77642491825 in words is "seventy-seven billion, six hundred forty-two million, four hundred ninety-one thousand, eight hundred twenty-five".