19920087 has 40 divisors (see below), whose sum is σ = 32989440. Its totient is φ = 11877840.

The previous prime is 19920079. The next prime is 19920119. The reversal of 19920087 is 78002991.

It is a happy number.

It is not a de Polignac number, because 19920087 - 2³ = 19920079 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19920287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 70248 + ... + 70530.

It is an arithmetic number, because the mean of its divisors is an integer number (824736).

Almost surely, 2^19920087 is an apocalyptic number.

19920087 is a deficient number, since it is larger than the sum of its proper divisors (13069353).

19920087 is a wasteful number, since it uses less digits than its factorization.

19920087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 385 (or 376 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 19920087 is about 4463.1924672817. The cubic root of 19920087 is about 271.0797503153.

The spelling of 19920087 in words is "nineteen million, nine hundred twenty thousand, eighty-seven".