1681625045 has 16 divisors (see below), whose sum is σ = 2070759600. Its totient is φ = 1310208000.

The previous prime is 1681625041. The next prime is 1681625051. The reversal of 1681625045 is 5405261861.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 248094001 + 1433531044 = 15751^2 + 37862^2 .

It is not a de Polignac number, because 1681625045 - 2² = 1681625041 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1681625041) 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, 116381 + ... + 130029.

It is an arithmetic number, because the mean of its divisors is an integer number (129422475).

Almost surely, 2^1681625045 is an apocalyptic number.

It is an amenable number.

1681625045 is a deficient number, since it is larger than the sum of its proper divisors (389134555).

1681625045 is a wasteful number, since it uses less digits than its factorization.

1681625045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14296.

The product of its (nonzero) digits is 57600, while the sum is 38.

The square root of 1681625045 is about 41007.6217915646. The cubic root of 1681625045 is about 1189.1675662641.

The spelling of 1681625045 in words is "one billion, six hundred eighty-one million, six hundred twenty-five thousand, forty-five".