1272237687721 has 32 divisors (see below), whose sum is σ = 1710119367936. Its totient is φ = 914056704000.

The previous prime is 1272237687709. The next prime is 1272237687737. The reversal of 1272237687721 is 1277867322721.

It is not a de Polignac number, because 1272237687721 - 2⁵ = 1272237687689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1272237687751) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 160561 + ... + 1603201.

It is an arithmetic number, because the mean of its divisors is an integer number (53441230248).

Almost surely, 2^{1272237687721} is an apocalyptic number.

1272237687721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1272237687721 is a deficient number, since it is larger than the sum of its proper divisors (437881680215).

1272237687721 is a wasteful number, since it uses less digits than its factorization.

1272237687721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1443553.

The product of its digits is 5531904, while the sum is 55.

The spelling of 1272237687721 in words is "one trillion, two hundred seventy-two billion, two hundred thirty-seven million, six hundred eighty-seven thousand, seven hundred twenty-one".