187713487421 has 2 divisors, whose sum is σ = 187713487422. Its totient is φ = 187713487420.

The previous prime is 187713487393. The next prime is 187713487439. The reversal of 187713487421 is 124784317781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 187089986521 + 623500900 = 432539^2 + 24970^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-187713487421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (187713487441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 93856743710 + 93856743711.

It is an arithmetic number, because the mean of its divisors is an integer number (93856743711).

Almost surely, 2^187713487421 is an apocalyptic number.

It is an amenable number.

187713487421 is a deficient number, since it is larger than the sum of its proper divisors (1).

187713487421 is an equidigital number, since it uses as much as digits as its factorization.

187713487421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2107392, while the sum is 53.

The spelling of 187713487421 in words is "one hundred eighty-seven billion, seven hundred thirteen million, four hundred eighty-seven thousand, four hundred twenty-one".