1213321987 has 2 divisors, whose sum is σ = 1213321988. Its totient is φ = 1213321986.

The previous prime is 1213321957. The next prime is 1213321997. The reversal of 1213321987 is 7891233121.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1213321987 - 2⁷ = 1213321859 is a prime.

It is not a weakly prime, because it can be changed into another prime (1213321937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606660993 + 606660994.

It is an arithmetic number, because the mean of its divisors is an integer number (606660994).

Almost surely, 2^1213321987 is an apocalyptic number.

1213321987 is a deficient number, since it is larger than the sum of its proper divisors (1).

1213321987 is an equidigital number, since it uses as much as digits as its factorization.

1213321987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 37.

The square root of 1213321987 is about 34832.7717386946. The cubic root of 1213321987 is about 1066.5765293733.

The spelling of 1213321987 in words is "one billion, two hundred thirteen million, three hundred twenty-one thousand, nine hundred eighty-seven".