1645629925 has 6 divisors (see below), whose sum is σ = 2040581138. Its totient is φ = 1316503920.

The previous prime is 1645629901. The next prime is 1645629949. The reversal of 1645629925 is 5299265461.

It is an interprime number because it is at equal distance from previous prime (1645629901) and next prime (1645629949).

It can be written as a sum of positive squares in 3 ways, for example, as 148791204 + 1496838721 = 12198^2 + 38689^2 .

It is not a de Polignac number, because 1645629925 - 2⁵ = 1645629893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 32912574 + ... + 32912623.

Almost surely, 2^1645629925 is an apocalyptic number.

It is an amenable number.

1645629925 is a deficient number, since it is larger than the sum of its proper divisors (394951213).

1645629925 is an equidigital number, since it uses as much as digits as its factorization.

1645629925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65825207 (or 65825202 counting only the distinct ones).

The product of its digits is 1166400, while the sum is 49.

The square root of 1645629925 is about 40566.3644538181. The cubic root of 1645629925 is about 1180.6216022555.

The spelling of 1645629925 in words is "one billion, six hundred forty-five million, six hundred twenty-nine thousand, nine hundred twenty-five".