1276721051 has 4 divisors (see below), whose sum is σ = 1277194704. Its totient is φ = 1276247400.

The previous prime is 1276721011. The next prime is 1276721057. The reversal of 1276721051 is 1501276721.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1276721051 - 2²² = 1272526747 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1276720999 and 1276721017.

It is not an unprimeable number, because it can be changed into a prime (1276721057) 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, 232760 + ... + 238181.

It is an arithmetic number, because the mean of its divisors is an integer number (319298676).

Almost surely, 2^1276721051 is an apocalyptic number.

1276721051 is a deficient number, since it is larger than the sum of its proper divisors (473653).

1276721051 is an equidigital number, since it uses as much as digits as its factorization.

1276721051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 473652.

The product of its (nonzero) digits is 5880, while the sum is 32.

The square root of 1276721051 is about 35731.2335499350. The cubic root of 1276721051 is about 1084.8391249937.

Adding to 1276721051 its reverse (1501276721), we get a palindrome (2777997772).

The spelling of 1276721051 in words is "one billion, two hundred seventy-six million, seven hundred twenty-one thousand, fifty-one".