981997261 has 8 divisors (see below), whose sum is σ = 1158485504. Its totient is φ = 814559760.

The previous prime is 981997207. The next prime is 981997267. The reversal of 981997261 is 162799189.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 981997261 - 2⁹ = 981996749 is a prime.

It is a super-2 number, since 2×981997261² = 1928637241223004242, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 981997199 and 981997208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (981997267) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2262450 + ... + 2262883.

It is an arithmetic number, because the mean of its divisors is an integer number (144810688).

Almost surely, 2^981997261 is an apocalyptic number.

It is an amenable number.

981997261 is a deficient number, since it is larger than the sum of its proper divisors (176488243).

981997261 is a wasteful number, since it uses less digits than its factorization.

981997261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4525371.

The product of its digits is 489888, while the sum is 52.

The square root of 981997261 is about 31336.8355294532. The cubic root of 981997261 is about 993.9627114983.

The spelling of 981997261 in words is "nine hundred eighty-one million, nine hundred ninety-seven thousand, two hundred sixty-one".