781106781101 has 4 divisors (see below), whose sum is σ = 782208483900. Its totient is φ = 780005078304.

The previous prime is 781106781083. The next prime is 781106781107. The reversal of 781106781101 is 101187601187.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 101187601187 = 7079 ⋅14294053.

It can be written as a sum of positive squares in 2 ways, for example, as 36727806025 + 744378975076 = 191645^2 + 862774^2 .

It is a cyclic number.

It is not a de Polignac number, because 781106781101 - 2³⁸ = 506228874157 is a prime.

It is a super-2 number, since 2×781106781101² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (781106781107) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 550850336 + ... + 550851753.

It is an arithmetic number, because the mean of its divisors is an integer number (195552120975).

Almost surely, 2^781106781101 is an apocalyptic number.

It is an amenable number.

781106781101 is a deficient number, since it is larger than the sum of its proper divisors (1101702799).

781106781101 is a wasteful number, since it uses less digits than its factorization.

781106781101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1101702798.

The product of its (nonzero) digits is 18816, while the sum is 41.

The spelling of 781106781101 in words is "seven hundred eighty-one billion, one hundred six million, seven hundred eighty-one thousand, one hundred one".