981867621 has 16 divisors (see below), whose sum is σ = 1503937664. Its totient is φ = 558157824.

The previous prime is 981867599. The next prime is 981867643. The reversal of 981867621 is 126768189.

It is an interprime number because it is at equal distance from previous prime (981867599) and next prime (981867643).

It is not a de Polignac number, because 981867621 - 2¹⁹ = 981343333 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (981867721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 117076 + ... + 125181.

It is an arithmetic number, because the mean of its divisors is an integer number (93996104).

Almost surely, 2^981867621 is an apocalyptic number.

It is an amenable number.

981867621 is a deficient number, since it is larger than the sum of its proper divisors (522070043).

981867621 is a wasteful number, since it uses less digits than its factorization.

981867621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242460.

The product of its digits is 290304, while the sum is 48.

The square root of 981867621 is about 31334.7669689755. The cubic root of 981867621 is about 993.9189696937.

The spelling of 981867621 in words is "nine hundred eighty-one million, eight hundred sixty-seven thousand, six hundred twenty-one".