981671623 has 4 divisors (see below), whose sum is σ = 981734688. Its totient is φ = 981608560.

The previous prime is 981671557. The next prime is 981671633. The reversal of 981671623 is 326176189.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 326176189 = 89 ⋅3664901.

It is a cyclic number.

It is not a de Polignac number, because 981671623 - 2²¹ = 979574471 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 981671623.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (981671633) 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, 10443 + ... + 45523.

It is an arithmetic number, because the mean of its divisors is an integer number (245433672).

Almost surely, 2^981671623 is an apocalyptic number.

981671623 is a deficient number, since it is larger than the sum of its proper divisors (63065).

981671623 is a wasteful number, since it uses less digits than its factorization.

981671623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63064.

The product of its digits is 108864, while the sum is 43.

The square root of 981671623 is about 31331.6393283211. The cubic root of 981671623 is about 993.8528307392.

The spelling of 981671623 in words is "nine hundred eighty-one million, six hundred seventy-one thousand, six hundred twenty-three".