7817313940 has 12 divisors (see below), whose sum is σ = 16416359316. Its totient is φ = 3126925568.

The previous prime is 7817313937. The next prime is 7817313943. The reversal of 7817313940 is 493137187.

It is an interprime number because it is at equal distance from previous prime (7817313937) and next prime (7817313943).

It can be written as a sum of positive squares in 2 ways, for example, as 4278729744 + 3538584196 = 65412^2 + 59486^2 .

It is a super-2 number, since 2×7817313940² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7817313943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 195432829 + ... + 195432868.

It is an arithmetic number, because the mean of its divisors is an integer number (1368029943).

Almost surely, 2^7817313940 is an apocalyptic number.

It is an amenable number.

7817313940 is an abundant number, since it is smaller than the sum of its proper divisors (8599045376).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7817313940 is a wasteful number, since it uses less digits than its factorization.

7817313940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 390865706 (or 390865704 counting only the distinct ones).

The product of its (nonzero) digits is 127008, while the sum is 43.

The square root of 7817313940 is about 88415.5752116108. The cubic root of 7817313940 is about 1984.6587861283.

The spelling of 7817313940 in words is "seven billion, eight hundred seventeen million, three hundred thirteen thousand, nine hundred forty".