1225161100 has 36 divisors (see below), whose sum is σ = 2814991704. Its totient is φ = 461236480.

The previous prime is 1225161089. The next prime is 1225161101. The reversal of 1225161100 is 11615221.

It is not an unprimeable number, because it can be changed into a prime (1225161101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 358642 + ... + 362041.

It is an arithmetic number, because the mean of its divisors is an integer number (78194214).

Almost surely, 2^1225161100 is an apocalyptic number.

1225161100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1225161100 is an abundant number, since it is smaller than the sum of its proper divisors (1589830604).

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

1225161100 is a wasteful number, since it uses less digits than its factorization.

1225161100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 720714 (or 720707 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 19.

The square root of 1225161100 is about 35002.3013529111. The cubic root of 1225161100 is about 1070.0343832664.

Adding to 1225161100 its reverse (11615221), we get a palindrome (1236776321).

The spelling of 1225161100 in words is "one billion, two hundred twenty-five million, one hundred sixty-one thousand, one hundred".