1644331153 has 2 divisors, whose sum is σ = 1644331154. Its totient is φ = 1644331152.

The previous prime is 1644331147. The next prime is 1644331181. The reversal of 1644331153 is 3511334461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1581493824 + 62837329 = 39768^2 + 7927^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1644331153 is a prime.

It is a super-3 number, since 3×1644331153³ (a number of 29 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (1644331133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 822165576 + 822165577.

It is an arithmetic number, because the mean of its divisors is an integer number (822165577).

Almost surely, 2^1644331153 is an apocalyptic number.

It is an amenable number.

1644331153 is a deficient number, since it is larger than the sum of its proper divisors (1).

1644331153 is an equidigital number, since it uses as much as digits as its factorization.

1644331153 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12960, while the sum is 31.

The square root of 1644331153 is about 40550.3533030231. The cubic root of 1644331153 is about 1180.3109285490.

The spelling of 1644331153 in words is "one billion, six hundred forty-four million, three hundred thirty-one thousand, one hundred fifty-three".