1605140225 has 24 divisors (see below), whose sum is σ = 2149388472. Its totient is φ = 1182067200.

The previous prime is 1605140209. The next prime is 1605140233. The reversal of 1605140225 is 5220415061.

It can be written as a sum of positive squares in 12 ways, for example, as 188897536 + 1416242689 = 13744^2 + 37633^2 .

It is not a de Polignac number, because 1605140225 - 2⁴ = 1605140209 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1605140194 and 1605140203.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 114605 + ... + 127845.

It is an arithmetic number, because the mean of its divisors is an integer number (89557853).

Almost surely, 2^1605140225 is an apocalyptic number.

It is an amenable number.

1605140225 is a deficient number, since it is larger than the sum of its proper divisors (544248247).

1605140225 is a wasteful number, since it uses less digits than its factorization.

1605140225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13637 (or 13632 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 1605140225 is about 40064.2012899296. The cubic root of 1605140225 is about 1170.8582654766.

Adding to 1605140225 its reverse (5220415061), we get a palindrome (6825555286).

The spelling of 1605140225 in words is "one billion, six hundred five million, one hundred forty thousand, two hundred twenty-five".