19401091 has 2 divisors, whose sum is σ = 19401092. Its totient is φ = 19401090.

The previous prime is 19401079. The next prime is 19401143. The reversal of 19401091 is 19010491.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19401091 - 2⁵ = 19401059 is a prime.

It is not a weakly prime, because it can be changed into another prime (19401491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9700545 + 9700546.

It is an arithmetic number, because the mean of its divisors is an integer number (9700546).

Almost surely, 2^19401091 is an apocalyptic number.

19401091 is a deficient number, since it is larger than the sum of its proper divisors (1).

19401091 is an equidigital number, since it uses as much as digits as its factorization.

19401091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 25.

The square root of 19401091 is about 4404.6669567630. Note that the first 3 decimals coincide. The cubic root of 19401091 is about 268.7047750834.

The spelling of 19401091 in words is "nineteen million, four hundred one thousand, ninety-one".