127772561 has 16 divisors (see below), whose sum is σ = 154986624. Its totient is φ = 102829824.

The previous prime is 127772543. The next prime is 127772569. The reversal of 127772561 is 165277721.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-127772561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (127772569) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 61211 + ... + 63263.

It is an arithmetic number, because the mean of its divisors is an integer number (9686664).

Almost surely, 2^127772561 is an apocalyptic number.

It is an amenable number.

127772561 is a deficient number, since it is larger than the sum of its proper divisors (27214063).

127772561 is a wasteful number, since it uses less digits than its factorization.

127772561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2600.

The product of its digits is 41160, while the sum is 38.

The square root of 127772561 is about 11303.6525512774. The cubic root of 127772561 is about 503.6697480049.

The spelling of 127772561 in words is "one hundred twenty-seven million, seven hundred seventy-two thousand, five hundred sixty-one".