1005221655 has 48 divisors (see below), whose sum is σ = 1805905920. Its totient is φ = 516715200.

The previous prime is 1005221639. The next prime is 1005221669. The reversal of 1005221655 is 5561225001.

1005221655 is a `hidden beast` number, since 1 + 0 + 0 + 5 + 2 + 2 + 1 + 655 = 666.

It is not a de Polignac number, because 1005221655 - 2⁴ = 1005221639 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 376716 + ... + 379374.

It is an arithmetic number, because the mean of its divisors is an integer number (37623040).

Almost surely, 2^1005221655 is an apocalyptic number.

1005221655 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1005221655 is a deficient number, since it is larger than the sum of its proper divisors (800684265).

1005221655 is a wasteful number, since it uses less digits than its factorization.

1005221655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2972 (or 2969 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 27.

The square root of 1005221655 is about 31705.2307198670. The cubic root of 1005221655 is about 1001.7375309045.

Adding to 1005221655 its reverse (5561225001), we get a palindrome (6566446656).

The spelling of 1005221655 in words is "one billion, five million, two hundred twenty-one thousand, six hundred fifty-five".