1870000187021 has 2 divisors, whose sum is σ = 1870000187022. Its totient is φ = 1870000187020.

The previous prime is 1870000186991. The next prime is 1870000187023. The reversal of 1870000187021 is 1207810000781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1407103653796 + 462896533225 = 1186214^2 + 680365^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1870000187021 is a prime.

It is a Sophie Germain prime.

Together with 1870000187023, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1870000187023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 935000093510 + 935000093511.

It is an arithmetic number, because the mean of its divisors is an integer number (935000093511).

Almost surely, 2^{1870000187021} is an apocalyptic number.

It is an amenable number.

1870000187021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1870000187021 is an equidigital number, since it uses as much as digits as its factorization.

1870000187021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6272, while the sum is 35.

The spelling of 1870000187021 in words is "one trillion, eight hundred seventy billion, one hundred eighty-seven thousand, twenty-one".