40121399 has 2 divisors, whose sum is σ = 40121400. Its totient is φ = 40121398.

The previous prime is 40121387. The next prime is 40121423. The reversal of 40121399 is 99312104.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40121399 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40121339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20060699 + 20060700.

It is an arithmetic number, because the mean of its divisors is an integer number (20060700).

Almost surely, 2^40121399 is an apocalyptic number.

40121399 is a deficient number, since it is larger than the sum of its proper divisors (1).

40121399 is an equidigital number, since it uses as much as digits as its factorization.

40121399 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 40121399 is about 6334.1454830151. The cubic root of 40121399 is about 342.3408221917.

The spelling of 40121399 in words is "forty million, one hundred twenty-one thousand, three hundred ninety-nine".