7135981 has 4 divisors (see below), whose sum is σ = 7141500. Its totient is φ = 7130464.

The previous prime is 7135967. The next prime is 7136021. The reversal of 7135981 is 1895317.

It is a happy number.

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.

It can be written as a sum of positive squares in 2 ways, for example, as 401956 + 6734025 = 634^2 + 2595^2 .

It is a cyclic number.

It is not a de Polignac number, because 7135981 - 2⁵ = 7135949 is a prime.

It is a super-2 number, since 2×7135981² = 101844449664722, which contains 22 as substring.

It is a Duffinian number.

7135981 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7135901) 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, 345 + ... + 3793.

It is an arithmetic number, because the mean of its divisors is an integer number (1785375).

Almost surely, 2^7135981 is an apocalyptic number.

It is an amenable number.

7135981 is a deficient number, since it is larger than the sum of its proper divisors (5519).

7135981 is a wasteful number, since it uses less digits than its factorization.

7135981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5518.

The product of its digits is 7560, while the sum is 34.

The square root of 7135981 is about 2671.3257008459. The cubic root of 7135981 is about 192.5238605382.

The spelling of 7135981 in words is "seven million, one hundred thirty-five thousand, nine hundred eighty-one".