1280315521 has 4 divisors (see below), whose sum is σ = 1280523712. Its totient is φ = 1280107332.

The previous prime is 1280315507. The next prime is 1280315527. The reversal of 1280315521 is 1255130821.

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 1280315521 - 2¹¹ = 1280313473 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 1280315521.

It is not an unprimeable number, because it can be changed into a prime (1280315527) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 94581 + ... + 107266.

It is an arithmetic number, because the mean of its divisors is an integer number (320130928).

Almost surely, 2^1280315521 is an apocalyptic number.

It is an amenable number.

1280315521 is a deficient number, since it is larger than the sum of its proper divisors (208191).

1280315521 is an equidigital number, since it uses as much as digits as its factorization.

1280315521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208190.

The product of its (nonzero) digits is 2400, while the sum is 28.

The square root of 1280315521 is about 35781.4969083184. The cubic root of 1280315521 is about 1085.8562534503.

The spelling of 1280315521 in words is "one billion, two hundred eighty million, three hundred fifteen thousand, five hundred twenty-one".