19980451 has 2 divisors, whose sum is σ = 19980452. Its totient is φ = 19980450.

The previous prime is 19980437. The next prime is 19980469. The reversal of 19980451 is 15408991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19980451 - 2¹³ = 19972259 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19980451.

It is not a weakly prime, because it can be changed into another prime (19980421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9990225 + 9990226.

It is an arithmetic number, because the mean of its divisors is an integer number (9990226).

Almost surely, 2^19980451 is an apocalyptic number.

19980451 is a deficient number, since it is larger than the sum of its proper divisors (1).

19980451 is an equidigital number, since it uses as much as digits as its factorization.

19980451 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12960, while the sum is 37.

The square root of 19980451 is about 4469.9497760042. The cubic root of 19980451 is about 271.3532925785.

The spelling of 19980451 in words is "nineteen million, nine hundred eighty thousand, four hundred fifty-one".