1838521782421 has 2 divisors, whose sum is σ = 1838521782422. Its totient is φ = 1838521782420.

The previous prime is 1838521782313. The next prime is 1838521782511. The reversal of 1838521782421 is 1242871258381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 934149312196 + 904372470225 = 966514^2 + 950985^2 .

It is a cyclic number.

It is not a de Polignac number, because 1838521782421 - 2³⁵ = 1804162044053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1838521782121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 919260891210 + 919260891211.

It is an arithmetic number, because the mean of its divisors is an integer number (919260891211).

Almost surely, 2^{1838521782421} is an apocalyptic number.

It is an amenable number.

1838521782421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1838521782421 is an equidigital number, since it uses as much as digits as its factorization.

1838521782421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1720320, while the sum is 52.

The spelling of 1838521782421 in words is "one trillion, eight hundred thirty-eight billion, five hundred twenty-one million, seven hundred eighty-two thousand, four hundred twenty-one".