69972781 has 2 divisors, whose sum is σ = 69972782. Its totient is φ = 69972780.

The previous prime is 69972751. The next prime is 69972817. The reversal of 69972781 is 18727996.

It is a happy number.

Together with next prime (69972817) 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., 68740681 + 1232100 = 8291^2 + 1110^2 .

It is a cyclic number.

It is not a de Polignac number, because 69972781 - 2¹⁹ = 69448493 is a prime.

It is a super-2 number, since 2×69972781² = 9792380161747922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (69972751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34986390 + 34986391.

It is an arithmetic number, because the mean of its divisors is an integer number (34986391).

Almost surely, 2^69972781 is an apocalyptic number.

It is an amenable number.

69972781 is a deficient number, since it is larger than the sum of its proper divisors (1).

69972781 is an equidigital number, since it uses as much as digits as its factorization.

69972781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 381024, while the sum is 49.

The square root of 69972781 is about 8364.9734608067. The cubic root of 69972781 is about 412.0751053106.

The spelling of 69972781 in words is "sixty-nine million, nine hundred seventy-two thousand, seven hundred eighty-one".