1663898893 has 2 divisors, whose sum is σ = 1663898894. Its totient is φ = 1663898892.

The previous prime is 1663898879. The next prime is 1663898903. The reversal of 1663898893 is 3988983661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1590573924 + 73324969 = 39882^2 + 8563^2 .

It is a cyclic number.

It is not a de Polignac number, because 1663898893 - 2²¹ = 1661801741 is a prime.

It is a super-2 number, since 2×1663898893² = 5537119052253250898, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1663898813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 831949446 + 831949447.

It is an arithmetic number, because the mean of its divisors is an integer number (831949447).

Almost surely, 2^1663898893 is an apocalyptic number.

It is an amenable number.

1663898893 is a deficient number, since it is larger than the sum of its proper divisors (1).

1663898893 is an equidigital number, since it uses as much as digits as its factorization.

1663898893 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13436928, while the sum is 61.

The square root of 1663898893 is about 40790.9167952867. The cubic root of 1663898893 is about 1184.9744261485.

The spelling of 1663898893 in words is "one billion, six hundred sixty-three million, eight hundred ninety-eight thousand, eight hundred ninety-three".