7817961 has 4 divisors (see below), whose sum is σ = 10423952. Its totient is φ = 5211972.

The previous prime is 7817951. The next prime is 7817963. The reversal of 7817961 is 1697187.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 7817961 - 2⁹ = 7817449 is a prime.

It is a super-2 number, since 2×7817961² = 122241028395042, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7817963) 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, 1302991 + ... + 1302996.

It is an arithmetic number, because the mean of its divisors is an integer number (2605988).

Almost surely, 2^7817961 is an apocalyptic number.

It is an amenable number.

7817961 is a deficient number, since it is larger than the sum of its proper divisors (2605991).

7817961 is a wasteful number, since it uses less digits than its factorization.

7817961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2605990.

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

The square root of 7817961 is about 2796.0616945983. The cubic root of 7817961 is about 198.4713543124.

It can be divided in two parts, 7817 and 961, that added together give a palindrome (8778).

The spelling of 7817961 in words is "seven million, eight hundred seventeen thousand, nine hundred sixty-one".