7821939499 has 16 divisors (see below), whose sum is σ = 8811970560. Its totient is φ = 6878592000.

The previous prime is 7821939493. The next prime is 7821939523. The reversal of 7821939499 is 9949391287.

It is a cyclic number.

It is not a de Polignac number, because 7821939499 - 2³ = 7821939491 is a prime.

It is a super-2 number, since 2×7821939499² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7821939491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1525462 + ... + 1530580.

It is an arithmetic number, because the mean of its divisors is an integer number (550748160).

Almost surely, 2^7821939499 is an apocalyptic number.

7821939499 is a deficient number, since it is larger than the sum of its proper divisors (990031061).

7821939499 is a wasteful number, since it uses less digits than its factorization.

7821939499 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9642.

The product of its digits is 8817984, while the sum is 61.

The square root of 7821939499 is about 88441.7293985141. The cubic root of 7821939499 is about 1985.0501544134.

The spelling of 7821939499 in words is "seven billion, eight hundred twenty-one million, nine hundred thirty-nine thousand, four hundred ninety-nine".