7866621020 has 12 divisors (see below), whose sum is σ = 16519904184. Its totient is φ = 3146648400.

The previous prime is 7866621019. The next prime is 7866621029. The reversal of 7866621020 is 201266687.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7866621029) 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 3 ways as a sum of consecutive naturals, for example, 196665506 + ... + 196665545.

It is an arithmetic number, because the mean of its divisors is an integer number (1376658682).

Almost surely, 2^7866621020 is an apocalyptic number.

It is an amenable number.

7866621020 is an abundant number, since it is smaller than the sum of its proper divisors (8653283164).

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

7866621020 is a wasteful number, since it uses less digits than its factorization.

7866621020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 393331060 (or 393331058 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 38.

The square root of 7866621020 is about 88693.9739779428. The cubic root of 7866621020 is about 1988.8227357477.

The spelling of 7866621020 in words is "seven billion, eight hundred sixty-six million, six hundred twenty-one thousand, twenty".