185193378421 has 2 divisors, whose sum is σ = 185193378422. Its totient is φ = 185193378420.

The previous prime is 185193378401. The next prime is 185193378457. The reversal of 185193378421 is 124873391581.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 168054903025 + 17138475396 = 409945^2 + 130914^2 .

It is a cyclic number.

It is not a de Polignac number, because 185193378421 - 2⁹ = 185193377909 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (185193378401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 92596689210 + 92596689211.

It is an arithmetic number, because the mean of its divisors is an integer number (92596689211).

Almost surely, 2^185193378421 is an apocalyptic number.

It is an amenable number.

185193378421 is a deficient number, since it is larger than the sum of its proper divisors (1).

185193378421 is an equidigital number, since it uses as much as digits as its factorization.

185193378421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1451520, while the sum is 52.

The spelling of 185193378421 in words is "one hundred eighty-five billion, one hundred ninety-three million, three hundred seventy-eight thousand, four hundred twenty-one".