77781522001 has 2 divisors, whose sum is σ = 77781522002. Its totient is φ = 77781522000.

The previous prime is 77781521981. The next prime is 77781522029. The reversal of 77781522001 is 10022518777.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55048421376 + 22733100625 = 234624^2 + 150775^2 .

It is a cyclic number.

It is not a de Polignac number, because 77781522001 - 2¹⁹ = 77780997713 is a prime.

It is not a weakly prime, because it can be changed into another prime (77781522031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38890761000 + 38890761001.

It is an arithmetic number, because the mean of its divisors is an integer number (38890761001).

Almost surely, 2^77781522001 is an apocalyptic number.

It is an amenable number.

77781522001 is a deficient number, since it is larger than the sum of its proper divisors (1).

77781522001 is an equidigital number, since it uses as much as digits as its factorization.

77781522001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54880, while the sum is 40.

The spelling of 77781522001 in words is "seventy-seven billion, seven hundred eighty-one million, five hundred twenty-two thousand, one".