1280753621 has 12 divisors (see below), whose sum is σ = 1514283660. Its totient is φ = 1079789760.

The previous prime is 1280753567. The next prime is 1280753657. The reversal of 1280753621 is 1263570821.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 82555396 + 1198198225 = 9086^2 + 34615^2 .

It is not a de Polignac number, because 1280753621 - 2¹⁰ = 1280752597 is a prime.

It is a super-2 number, since 2×1280753621² = 3280659675409223282, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1280753671) 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 11 ways as a sum of consecutive naturals, for example, 211256 + ... + 217233.

It is an arithmetic number, because the mean of its divisors is an integer number (126190305).

Almost surely, 2^1280753621 is an apocalyptic number.

It is an amenable number.

1280753621 is a deficient number, since it is larger than the sum of its proper divisors (233530039).

1280753621 is an equidigital number, since it uses as much as digits as its factorization.

1280753621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 428564 (or 428557 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 35.

The square root of 1280753621 is about 35787.6182638633. The cubic root of 1280753621 is about 1085.9800925527.

The spelling of 1280753621 in words is "one billion, two hundred eighty million, seven hundred fifty-three thousand, six hundred twenty-one".