1611661225 has 48 divisors (see below), whose sum is σ = 2205216000. Its totient is φ = 1163635200.

The previous prime is 1611661193. The next prime is 1611661229. The reversal of 1611661225 is 5221661161.

It is not a de Polignac number, because 1611661225 - 2⁵ = 1611661193 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1611661229) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1087485 + ... + 1088965.

It is an arithmetic number, because the mean of its divisors is an integer number (45942000).

Almost surely, 2^1611661225 is an apocalyptic number.

It is an amenable number.

1611661225 is a deficient number, since it is larger than the sum of its proper divisors (593554775).

1611661225 is a wasteful number, since it uses less digits than its factorization.

1611661225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1618 (or 1613 counting only the distinct ones).

The product of its digits is 4320, while the sum is 31.

The square root of 1611661225 is about 40145.5006818946. The cubic root of 1611661225 is about 1172.4416890364.

The spelling of 1611661225 in words is "one billion, six hundred eleven million, six hundred sixty-one thousand, two hundred twenty-five".