40269781 has 2 divisors, whose sum is σ = 40269782. Its totient is φ = 40269780.

The previous prime is 40269767. The next prime is 40269833. The reversal of 40269781 is 18796204.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 37576900 + 2692881 = 6130^2 + 1641^2 .

It is a cyclic number.

It is not a de Polignac number, because 40269781 - 2¹⁵ = 40237013 is a prime.

It is a super-2 number, since 2×40269781² = 3243310523575922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 40269781.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40969781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20134890 + 20134891.

It is an arithmetic number, because the mean of its divisors is an integer number (20134891).

Almost surely, 2^40269781 is an apocalyptic number.

It is an amenable number.

40269781 is a deficient number, since it is larger than the sum of its proper divisors (1).

40269781 is an equidigital number, since it uses as much as digits as its factorization.

40269781 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 40269781 is about 6345.8475399272. The cubic root of 40269781 is about 342.7623322748.

The spelling of 40269781 in words is "forty million, two hundred sixty-nine thousand, seven hundred eighty-one".