55785651638 has 4 divisors (see below), whose sum is σ = 83678477460. Its totient is φ = 27892825818.

The previous prime is 55785651617. The next prime is 55785651641. The reversal of 55785651638 is 83615658755.

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

It is a super-2 number, since 2×55785651638² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13946412908 + ... + 13946412911.

It is an arithmetic number, because the mean of its divisors is an integer number (20919619365).

Almost surely, 2^55785651638 is an apocalyptic number.

55785651638 is a deficient number, since it is larger than the sum of its proper divisors (27892825822).

55785651638 is a wasteful number, since it uses less digits than its factorization.

55785651638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27892825821.

The product of its digits is 30240000, while the sum is 59.

The spelling of 55785651638 in words is "fifty-five billion, seven hundred eighty-five million, six hundred fifty-one thousand, six hundred thirty-eight".