7761981 has 8 divisors (see below), whose sum is σ = 10524960. Its totient is φ = 5086832.

The previous prime is 7761967. The next prime is 7761989. The reversal of 7761981 is 1891677.

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

It is a cyclic number.

It is not a de Polignac number, because 7761981 - 2⁶ = 7761917 is a prime.

It is a super-2 number, since 2×7761981² = 120496698088722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7761989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21750 + ... + 22103.

It is an arithmetic number, because the mean of its divisors is an integer number (1315620).

Almost surely, 2^7761981 is an apocalyptic number.

It is an amenable number.

7761981 is a deficient number, since it is larger than the sum of its proper divisors (2762979).

7761981 is a wasteful number, since it uses less digits than its factorization.

7761981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43915.

The product of its digits is 21168, while the sum is 39.

The square root of 7761981 is about 2786.0332015251. The cubic root of 7761981 is about 197.9965053969.

The spelling of 7761981 in words is "seven million, seven hundred sixty-one thousand, nine hundred eighty-one".