981561774101 has 4 divisors (see below), whose sum is σ = 998198414400. Its totient is φ = 964925133804.

The previous prime is 981561774077. The next prime is 981561774103. The reversal of 981561774101 is 101477165189.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-981561774101 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 981561774101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (981561774103) 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, 8318320061 + ... + 8318320178.

It is an arithmetic number, because the mean of its divisors is an integer number (249549603600).

Almost surely, 2^981561774101 is an apocalyptic number.

It is an amenable number.

981561774101 is a deficient number, since it is larger than the sum of its proper divisors (16636640299).

981561774101 is a wasteful number, since it uses less digits than its factorization.

981561774101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16636640298.

The product of its (nonzero) digits is 423360, while the sum is 50.

The spelling of 981561774101 in words is "nine hundred eighty-one billion, five hundred sixty-one million, seven hundred seventy-four thousand, one hundred one".