9905220655 has 16 divisors (see below), whose sum is σ = 12996403200. Its totient is φ = 7187369760.

The previous prime is 9905220653. The next prime is 9905220707. The reversal of 9905220655 is 5560225099.

It is not a de Polignac number, because 9905220655 - 2¹ = 9905220653 is a prime.

It is a super-2 number, since 2×9905220655² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9905220653) 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, 180975 + ... + 229264.

It is an arithmetic number, because the mean of its divisors is an integer number (812275200).

Almost surely, 2^9905220655 is an apocalyptic number.

9905220655 is a deficient number, since it is larger than the sum of its proper divisors (3091182545).

9905220655 is a wasteful number, since it uses less digits than its factorization.

9905220655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410694.

The product of its (nonzero) digits is 243000, while the sum is 43.

The square root of 9905220655 is about 99524.9750313960. The cubic root of 9905220655 is about 2147.6065418403.

The spelling of 9905220655 in words is "nine billion, nine hundred five million, two hundred twenty thousand, six hundred fifty-five".