19945487 has 2 divisors, whose sum is σ = 19945488. Its totient is φ = 19945486.

The previous prime is 19945469. The next prime is 19945489. The reversal of 19945487 is 78454991.

It is a strong prime.

It is an emirp because it is prime and its reverse (78454991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19945487 - 2¹⁴ = 19929103 is a prime.

Together with 19945489, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19945489) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9972743 + 9972744.

It is an arithmetic number, because the mean of its divisors is an integer number (9972744).

Almost surely, 2^19945487 is an apocalyptic number.

19945487 is a deficient number, since it is larger than the sum of its proper divisors (1).

19945487 is an equidigital number, since it uses as much as digits as its factorization.

19945487 is an evil number, because the sum of its binary digits is even.

The product of its digits is 362880, while the sum is 47.

The square root of 19945487 is about 4466.0370576161. The cubic root of 19945487 is about 271.1949188419.

The spelling of 19945487 in words is "nineteen million, nine hundred forty-five thousand, four hundred eighty-seven".