19902051 has 16 divisors (see below), whose sum is σ = 31753120. Its totient is φ = 12247200.

The previous prime is 19902023. The next prime is 19902059. The reversal of 19902051 is 15020991.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-19902051 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19902059) 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, 28000 + ... + 28701.

It is an arithmetic number, because the mean of its divisors is an integer number (1984570).

Almost surely, 2^19902051 is an apocalyptic number.

19902051 is a deficient number, since it is larger than the sum of its proper divisors (11851069).

19902051 is a wasteful number, since it uses less digits than its factorization.

19902051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56723 (or 56717 counting only the distinct ones).

The product of its (nonzero) digits is 810, while the sum is 27.

The square root of 19902051 is about 4461.1714829179. The cubic root of 19902051 is about 270.9979121402.

The spelling of 19902051 in words is "nineteen million, nine hundred two thousand, fifty-one".