28055851638 has 32 divisors (see below), whose sum is σ = 60794084736. Its totient is φ = 8597140608.

The previous prime is 28055851619. The next prime is 28055851639. The reversal of 28055851638 is 83615855082.

It is a super-2 number, since 2×28055851638² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28055851639) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3193956 + ... + 3202727.

It is an arithmetic number, because the mean of its divisors is an integer number (1899815148).

Almost surely, 2^28055851638 is an apocalyptic number.

28055851638 is an abundant number, since it is smaller than the sum of its proper divisors (32738233098).

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

28055851638 is a wasteful number, since it uses less digits than its factorization.

28055851638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6396748.

The product of its (nonzero) digits is 2304000, while the sum is 51.

The spelling of 28055851638 in words is "twenty-eight billion, fifty-five million, eight hundred fifty-one thousand, six hundred thirty-eight".