1203121653 has 4 divisors (see below), whose sum is σ = 1604162208. Its totient is φ = 802081100.

The previous prime is 1203121649. The next prime is 1203121691. The reversal of 1203121653 is 3561213021.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1203121653 - 2² = 1203121649 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1203121453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 200520273 + ... + 200520278.

It is an arithmetic number, because the mean of its divisors is an integer number (401040552).

Almost surely, 2^1203121653 is an apocalyptic number.

It is an amenable number.

1203121653 is a deficient number, since it is larger than the sum of its proper divisors (401040555).

1203121653 is an equidigital number, since it uses as much as digits as its factorization.

1203121653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 401040554.

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 1203121653 is about 34686.0440667425. The cubic root of 1203121653 is about 1063.5792300121.

Adding to 1203121653 its reverse (3561213021), we get a palindrome (4764334674).

The spelling of 1203121653 in words is "one billion, two hundred three million, one hundred twenty-one thousand, six hundred fifty-three".