1625538609 has 12 divisors (see below), whose sum is σ = 2350247952. Its totient is φ = 1082655000.

The previous prime is 1625538581. The next prime is 1625538611. The reversal of 1625538609 is 9068355261.

1625538609 is a `hidden beast` number, since 1 + 6 + 2 + 5 + 5 + 38 + 609 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-1625538609 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1625538619) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 76467 + ... + 95384.

It is an arithmetic number, because the mean of its divisors is an integer number (195853996).

Almost surely, 2^1625538609 is an apocalyptic number.

It is an amenable number.

1625538609 is a deficient number, since it is larger than the sum of its proper divisors (724709343).

1625538609 is a wasteful number, since it uses less digits than its factorization.

1625538609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172908 (or 172905 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 45.

The square root of 1625538609 is about 40317.9688104448. The cubic root of 1625538609 is about 1175.7972218222.

The spelling of 1625538609 in words is "one billion, six hundred twenty-five million, five hundred thirty-eight thousand, six hundred nine".