1663429381 has 2 divisors, whose sum is σ = 1663429382. Its totient is φ = 1663429380.

The previous prime is 1663429343. The next prime is 1663429399. The reversal of 1663429381 is 1839243661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1493126881 + 170302500 = 38641^2 + 13050^2 .

It is an emirp because it is prime and its reverse (1839243661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1663429381 - 2²³ = 1655040773 is a prime.

It is a super-2 number, since 2×1663429381² = 5533994611148086322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1663429321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 831714690 + 831714691.

It is an arithmetic number, because the mean of its divisors is an integer number (831714691).

Almost surely, 2^1663429381 is an apocalyptic number.

It is an amenable number.

1663429381 is a deficient number, since it is larger than the sum of its proper divisors (1).

1663429381 is an equidigital number, since it uses as much as digits as its factorization.

1663429381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 186624, while the sum is 43.

The square root of 1663429381 is about 40785.1612844672. The cubic root of 1663429381 is about 1184.8629586281.

The spelling of 1663429381 in words is "one billion, six hundred sixty-three million, four hundred twenty-nine thousand, three hundred eighty-one".