81411778107 has 32 divisors (see below), whose sum is σ = 131625826560. Its totient is φ = 49321258560.

The previous prime is 81411778103. The next prime is 81411778117. The reversal of 81411778107 is 70187711418.

It is not a de Polignac number, because 81411778107 - 2² = 81411778103 is a prime.

It is a super-2 number, since 2×81411778107² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81411778103) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 729948 + ... + 834054.

It is an arithmetic number, because the mean of its divisors is an integer number (4113307080).

Almost surely, 2^81411778107 is an apocalyptic number.

81411778107 is a deficient number, since it is larger than the sum of its proper divisors (50214048453).

81411778107 is a wasteful number, since it uses less digits than its factorization.

81411778107 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106760 (or 106754 counting only the distinct ones).

The product of its (nonzero) digits is 87808, while the sum is 45.

The spelling of 81411778107 in words is "eighty-one billion, four hundred eleven million, seven hundred seventy-eight thousand, one hundred seven".