1204531621 has 2 divisors, whose sum is σ = 1204531622. Its totient is φ = 1204531620.

The previous prime is 1204531613. The next prime is 1204531637. The reversal of 1204531621 is 1261354021.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1187836225 + 16695396 = 34465^2 + 4086^2 .

It is a cyclic number.

It is not a de Polignac number, because 1204531621 - 2³ = 1204531613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1204531121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 602265810 + 602265811.

It is an arithmetic number, because the mean of its divisors is an integer number (602265811).

Almost surely, 2^1204531621 is an apocalyptic number.

It is an amenable number.

1204531621 is a deficient number, since it is larger than the sum of its proper divisors (1).

1204531621 is an equidigital number, since it uses as much as digits as its factorization.

1204531621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 1204531621 is about 34706.3628316192. The cubic root of 1204531621 is about 1063.9945460765.

Adding to 1204531621 its reverse (1261354021), we get a palindrome (2465885642).

The spelling of 1204531621 in words is "one billion, two hundred four million, five hundred thirty-one thousand, six hundred twenty-one".