40969781 has 2 divisors, whose sum is σ = 40969782. Its totient is φ = 40969780.

The previous prime is 40969771. The next prime is 40969801. The reversal of 40969781 is 18796904.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40436881 + 532900 = 6359^2 + 730^2 .

It is a cyclic number.

It is not a de Polignac number, because 40969781 - 2¹⁰ = 40968757 is a prime.

It is a super-2 number, since 2×40969781² = 3357045910375922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40969751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20484890 + 20484891.

It is an arithmetic number, because the mean of its divisors is an integer number (20484891).

Almost surely, 2^40969781 is an apocalyptic number.

It is an amenable number.

40969781 is a deficient number, since it is larger than the sum of its proper divisors (1).

40969781 is an equidigital number, since it uses as much as digits as its factorization.

40969781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108864, while the sum is 44.

The square root of 40969781 is about 6400.7640950124. The cubic root of 40969781 is about 344.7369864059.

The spelling of 40969781 in words is "forty million, nine hundred sixty-nine thousand, seven hundred eighty-one".