69042781 has 2 divisors, whose sum is σ = 69042782. Its totient is φ = 69042780.

The previous prime is 69042773. The next prime is 69042817. The reversal of 69042781 is 18724096.

Together with next prime (69042817) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60310756 + 8732025 = 7766^2 + 2955^2 .

It is a cyclic number.

It is not a de Polignac number, because 69042781 - 2³ = 69042773 is a prime.

It is a super-2 number, since 2×69042781² = 9533811216427922, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 69042781.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (69040781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34521390 + 34521391.

It is an arithmetic number, because the mean of its divisors is an integer number (34521391).

Almost surely, 2^69042781 is an apocalyptic number.

It is an amenable number.

69042781 is a deficient number, since it is larger than the sum of its proper divisors (1).

69042781 is an equidigital number, since it uses as much as digits as its factorization.

69042781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 69042781 is about 8309.1985774803. The cubic root of 69042781 is about 410.2413431345.

The spelling of 69042781 in words is "sixty-nine million, forty-two thousand, seven hundred eighty-one".