19910051 has 16 divisors (see below), whose sum is σ = 23502528. Its totient is φ = 16512000.

The previous prime is 19910039. The next prime is 19910053. The reversal of 19910051 is 15001991.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 19910051 - 2²² = 15715747 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19910051.

It is not an unprimeable number, because it can be changed into a prime (19910053) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49451 + ... + 49851.

It is an arithmetic number, because the mean of its divisors is an integer number (1468908).

Almost surely, 2^19910051 is an apocalyptic number.

19910051 is a deficient number, since it is larger than the sum of its proper divisors (3592477).

19910051 is a wasteful number, since it uses less digits than its factorization.

19910051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 622.

The product of its (nonzero) digits is 405, while the sum is 26.

The square root of 19910051 is about 4462.0680183072. The cubic root of 19910051 is about 271.0342181617.

The spelling of 19910051 in words is "nineteen million, nine hundred ten thousand, fifty-one".