1653397649 has 4 divisors (see below), whose sum is σ = 1653978420. Its totient is φ = 1652816880.

The previous prime is 1653397639. The next prime is 1653397657. The reversal of 1653397649 is 9467933561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9467933561 = 829 ⋅11420909.

It can be written as a sum of positive squares in 2 ways, for example, as 358837249 + 1294560400 = 18943^2 + 35980^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1653397649 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1653397649.

It is not an unprimeable number, because it can be changed into a prime (1653397609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 286094 + ... + 291815.

It is an arithmetic number, because the mean of its divisors is an integer number (413494605).

Almost surely, 2^1653397649 is an apocalyptic number.

It is an amenable number.

1653397649 is a deficient number, since it is larger than the sum of its proper divisors (580771).

1653397649 is an equidigital number, since it uses as much as digits as its factorization.

1653397649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 580770.

The product of its digits is 3674160, while the sum is 53.

The square root of 1653397649 is about 40661.9926835860. The cubic root of 1653397649 is about 1182.4762823486.

The spelling of 1653397649 in words is "one billion, six hundred fifty-three million, three hundred ninety-seven thousand, six hundred forty-nine".