840420149 has 2 divisors, whose sum is σ = 840420150. Its totient is φ = 840420148.

The previous prime is 840420121. The next prime is 840420181. The reversal of 840420149 is 941024048.

It is an a-pointer prime, because the next prime (840420181) can be obtained adding 840420149 to its sum of digits (32).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 840420100 + 49 = 28990^2 + 7^2 .

It is a cyclic number.

It is not a de Polignac number, because 840420149 - 2⁸ = 840419893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (840420649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 420210074 + 420210075.

It is an arithmetic number, because the mean of its divisors is an integer number (420210075).

Almost surely, 2^840420149 is an apocalyptic number.

It is an amenable number.

840420149 is a deficient number, since it is larger than the sum of its proper divisors (1).

840420149 is an equidigital number, since it uses as much as digits as its factorization.

840420149 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9216, while the sum is 32.

The square root of 840420149 is about 28990.0008451190. Note that the first 3 decimals coincide. The cubic root of 840420149 is about 943.6960820972.

It can be divided in two parts, 8404201 and 49, that multiplied together give a square (411805849 = 20293²).

The spelling of 840420149 in words is "eight hundred forty million, four hundred twenty thousand, one hundred forty-nine".