1653642225 has 27 divisors (see below), whose sum is σ = 2962949899. Its totient is φ = 881617200.

The previous prime is 1653642203. The next prime is 1653642233. The reversal of 1653642225 is 5222463561.

The square root of 1653642225 is 40665.

It is a perfect power (a square), and thus also a powerful number.

1653642225 is a `hidden beast` number, since 1 + 6 + 5 + 3 + 642 + 2 + 2 + 5 = 666.

It can be written as a sum of positive squares in only one way, i.e., 595311201 + 1058331024 = 24399^2 + 32532^2 .

It is not a de Polignac number, because 1653642225 - 2⁷ = 1653642097 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1653642225.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 608620 + ... + 611330.

Almost surely, 2^1653642225 is an apocalyptic number.

1653642225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1653642225 is the 40665-th square number.

1653642225 is the 20333-rd centered octagonal number.

It is an amenable number.

1653642225 is a deficient number, since it is larger than the sum of its proper divisors (1309307674).

1653642225 is an frugal number, since it uses more digits than its factorization.

1653642225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5438 (or 2719 counting only the distinct ones).

The product of its digits is 86400, while the sum is 36.

The cubic root of 1653642225 is about 1182.5345847299.

Multiplying 1653642225 by its sum of digits (36), we get a square (59531120100 = 243990²).

The spelling of 1653642225 in words is "one billion, six hundred fifty-three million, six hundred forty-two thousand, two hundred twenty-five".