122681781 has 12 divisors (see below), whose sum is σ = 177597420. Its totient is φ = 81607680.

The previous prime is 122681761. The next prime is 122681791. The reversal of 122681781 is 187186221.

It can be written as a sum of positive squares in 2 ways, for example, as 52272900 + 70408881 = 7230^2 + 8391^2 .

It is not a de Polignac number, because 122681781 - 2⁵ = 122681749 is a prime.

It is a super-2 number, since 2×122681781² = 30101638778663922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (122681731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10636 + ... + 18933.

It is an arithmetic number, because the mean of its divisors is an integer number (14799785).

Almost surely, 2^122681781 is an apocalyptic number.

It is an amenable number.

122681781 is a deficient number, since it is larger than the sum of its proper divisors (54915639).

122681781 is a wasteful number, since it uses less digits than its factorization.

122681781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30036 (or 30033 counting only the distinct ones).

The product of its digits is 10752, while the sum is 36.

The square root of 122681781 is about 11076.1807948408. The cubic root of 122681781 is about 496.8897339407.

The spelling of 122681781 in words is "one hundred twenty-two million, six hundred eighty-one thousand, seven hundred eighty-one".