1272442721 has 4 divisors (see below), whose sum is σ = 1388119344. Its totient is φ = 1156766100.

The previous prime is 1272442697. The next prime is 1272442733.

1272442721 is nontrivially palindromic in base 10.

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 1272442721 - 2¹⁰ = 1272441697 is a prime.

It is a super-2 number, since 2×1272442721² = 3238220956451767682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1272444721) 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, 57838295 + ... + 57838316.

It is an arithmetic number, because the mean of its divisors is an integer number (347029836).

Almost surely, 2^1272442721 is an apocalyptic number.

1272442721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1272442721 is a deficient number, since it is larger than the sum of its proper divisors (115676623).

1272442721 is a wasteful number, since it uses less digits than its factorization.

1272442721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115676622.

The product of its digits is 12544, while the sum is 32.

The square root of 1272442721 is about 35671.3151005118. The cubic root of 1272442721 is about 1083.6259929054.

The spelling of 1272442721 in words is "one billion, two hundred seventy-two million, four hundred forty-two thousand, seven hundred twenty-one".