1640625 has 32 divisors (see below), whose sum is σ = 3124992. Its totient is φ = 750000.

The previous prime is 1640623. The next prime is 1640633. The reversal of 1640625 is 5260461.

It is not a de Polignac number, because 1640625 - 2¹ = 1640623 is a prime.

1640625 is a lucky number.

It is a plaindrome in base 13.

It is a nialpdrome in base 5.

It is a junction number, because it is equal to n+sod(n) for n = 1640595 and 1640604.

It is not an unprimeable number, because it can be changed into a prime (1640621) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 234372 + ... + 234378.

It is an arithmetic number, because the mean of its divisors is an integer number (97656).

2^1640625 is an apocalyptic number.

1640625 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1640625 is a deficient number, since it is larger than the sum of its proper divisors (1484367).

1640625 is an frugal number, since it uses more digits than its factorization.

1640625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45 (or 15 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 1640625 is about 1280.8688457449. The cubic root of 1640625 is about 117.9423495079.

The spelling of 1640625 in words is "one million, six hundred forty thousand, six hundred twenty-five".