1978398229 has 2 divisors, whose sum is σ = 1978398230. Its totient is φ = 1978398228.

The previous prime is 1978398187. The next prime is 1978398283. The reversal of 1978398229 is 9228938791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1323140625 + 655257604 = 36375^2 + 25598^2 .

It is a cyclic number.

It is not a de Polignac number, because 1978398229 - 2¹⁵ = 1978365461 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1978398329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 989199114 + 989199115.

It is an arithmetic number, because the mean of its divisors is an integer number (989199115).

Almost surely, 2^1978398229 is an apocalyptic number.

It is an amenable number.

1978398229 is a deficient number, since it is larger than the sum of its proper divisors (1).

1978398229 is an equidigital number, since it uses as much as digits as its factorization.

1978398229 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3919104, while the sum is 58.

The square root of 1978398229 is about 44479.1887178712. The cubic root of 1978398229 is about 1255.3685322672.

The spelling of 1978398229 in words is "one billion, nine hundred seventy-eight million, three hundred ninety-eight thousand, two hundred twenty-nine".