6556851638 has 16 divisors (see below), whose sum is σ = 10392814080. Its totient is φ = 3096189096.

The previous prime is 6556851577. The next prime is 6556851671. The reversal of 6556851638 is 8361586556.

It is a self number, because there is not a number n which added to its sum of digits gives 6556851638.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 898520 + ... + 905787.

It is an arithmetic number, because the mean of its divisors is an integer number (649550880).

Almost surely, 2^6556851638 is an apocalyptic number.

6556851638 is a deficient number, since it is larger than the sum of its proper divisors (3835962442).

6556851638 is a wasteful number, since it uses less digits than its factorization.

6556851638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1804411.

The product of its digits is 5184000, while the sum is 53.

The square root of 6556851638 is about 80974.3887781810. The cubic root of 6556851638 is about 1871.6808015171.

The spelling of 6556851638 in words is "six billion, five hundred fifty-six million, eight hundred fifty-one thousand, six hundred thirty-eight".