1225558845 has 72 divisors (see below), whose sum is σ = 2489777784. Its totient is φ = 556028928.

The previous prime is 1225558777. The next prime is 1225558861. The reversal of 1225558845 is 5488555221.

1225558845 is a `hidden beast` number, since 1 + 2 + 25 + 5 + 588 + 45 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 161951076 + 1063607769 = 12726^2 + 32613^2 .

It is not a de Polignac number, because 1225558845 - 2⁹ = 1225558333 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 1225558845.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 300057 + ... + 304113.

It is an arithmetic number, because the mean of its divisors is an integer number (34580247).

Almost surely, 2^1225558845 is an apocalyptic number.

1225558845 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1225558845 is an abundant number, since it is smaller than the sum of its proper divisors (1264218939).

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

1225558845 is a wasteful number, since it uses less digits than its factorization.

1225558845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4219 (or 4209 counting only the distinct ones).

The product of its digits is 640000, while the sum is 45.

The square root of 1225558845 is about 35007.9825896895. The cubic root of 1225558845 is about 1070.1501652582.

The spelling of 1225558845 in words is "one billion, two hundred twenty-five million, five hundred fifty-eight thousand, eight hundred forty-five".