19920851 has 2 divisors, whose sum is σ = 19920852. Its totient is φ = 19920850.

The previous prime is 19920847. The next prime is 19920863. The reversal of 19920851 is 15802991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19920851 - 2² = 19920847 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (19920871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9960425 + 9960426.

It is an arithmetic number, because the mean of its divisors is an integer number (9960426).

Almost surely, 2^19920851 is an apocalyptic number.

19920851 is a deficient number, since it is larger than the sum of its proper divisors (1).

19920851 is an equidigital number, since it uses as much as digits as its factorization.

19920851 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6480, while the sum is 35.

The square root of 19920851 is about 4463.2780554207. The cubic root of 19920851 is about 271.0832158671.

The spelling of 19920851 in words is "nineteen million, nine hundred twenty thousand, eight hundred fifty-one".