1272738889 has 2 divisors, whose sum is σ = 1272738890. Its totient is φ = 1272738888.

The previous prime is 1272738773. The next prime is 1272738919. The reversal of 1272738889 is 9888372721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1038128400 + 234610489 = 32220^2 + 15317^2 .

It is a cyclic number.

It is not a de Polignac number, because 1272738889 - 2¹⁵ = 1272706121 is a prime.

It is not a weakly prime, because it can be changed into another prime (1272708889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 636369444 + 636369445.

It is an arithmetic number, because the mean of its divisors is an integer number (636369445).

Almost surely, 2^1272738889 is an apocalyptic number.

It is an amenable number.

1272738889 is a deficient number, since it is larger than the sum of its proper divisors (1).

1272738889 is an equidigital number, since it uses as much as digits as its factorization.

1272738889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2709504, while the sum is 55.

The square root of 1272738889 is about 35675.4662057835. The cubic root of 1272738889 is about 1083.7100596748.

The spelling of 1272738889 in words is "one billion, two hundred seventy-two million, seven hundred thirty-eight thousand, eight hundred eighty-nine".