7851006638513 has 4 divisors (see below), whose sum is σ = 8042494605348. Its totient is φ = 7659518671680.

The previous prime is 7851006638507. The next prime is 7851006638543. The reversal of 7851006638513 is 3158366001587.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4099843387249 + 3751163251264 = 2024807^2 + 1936792^2 .

It is a cyclic number.

It is not a de Polignac number, because 7851006638513 - 2²² = 7851002444209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7851006638543) 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, 95743983356 + ... + 95743983437.

It is an arithmetic number, because the mean of its divisors is an integer number (2010623651337).

Almost surely, 2^{7851006638513} is an apocalyptic number.

It is an amenable number.

7851006638513 is a deficient number, since it is larger than the sum of its proper divisors (191487966835).

7851006638513 is a wasteful number, since it uses less digits than its factorization.

7851006638513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191487966834.

The product of its (nonzero) digits is 3628800, while the sum is 53.

The spelling of 7851006638513 in words is "seven trillion, eight hundred fifty-one billion, six million, six hundred thirty-eight thousand, five hundred thirteen".