1661046225 has 24 divisors (see below), whose sum is σ = 2766325920. Its totient is φ = 879419520.

The previous prime is 1661046221. The next prime is 1661046239. The reversal of 1661046225 is 5226401661.

It is not a de Polignac number, because 1661046225 - 2² = 1661046221 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1661046221) 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 23 ways as a sum of consecutive naturals, for example, 70555 + ... + 91104.

It is an arithmetic number, because the mean of its divisors is an integer number (115263580).

Almost surely, 2^1661046225 is an apocalyptic number.

1661046225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1661046225 is a deficient number, since it is larger than the sum of its proper divisors (1105279695).

1661046225 is a wasteful number, since it uses less digits than its factorization.

1661046225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161809 (or 161804 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 1661046225 is about 40755.9348438973. The cubic root of 1661046225 is about 1184.2968464615.

Adding to 1661046225 its reverse (5226401661), we get a palindrome (6887447886).

It can be divided in two parts, 16610 and 46225, that added together give a triangular number (62835 = T₃₅₄).

The spelling of 1661046225 in words is "one billion, six hundred sixty-one million, forty-six thousand, two hundred twenty-five".