40400069 has 2 divisors, whose sum is σ = 40400070. Its totient is φ = 40400068.

The previous prime is 40400057. The next prime is 40400071. The reversal of 40400069 is 96000404.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24900100 + 15499969 = 4990^2 + 3937^2 .

It is a cyclic number.

It is not a de Polignac number, because 40400069 - 2⁴ = 40400053 is a prime.

It is a super-2 number, since 2×40400069² = 3264331150409522, which contains 22 as substring.

Together with 40400071, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40400089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20200034 + 20200035.

It is an arithmetic number, because the mean of its divisors is an integer number (20200035).

Almost surely, 2^40400069 is an apocalyptic number.

It is an amenable number.

40400069 is a deficient number, since it is larger than the sum of its proper divisors (1).

40400069 is an equidigital number, since it uses as much as digits as its factorization.

40400069 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 40400069 is about 6356.1048606832. The cubic root of 40400069 is about 343.1315896713.

The spelling of 40400069 in words is "forty million, four hundred thousand, sixty-nine".