19420638 has 8 divisors (see below), whose sum is σ = 38841288. Its totient is φ = 6473544.

The previous prime is 19420637. The next prime is 19420657. The reversal of 19420638 is 83602491.

It is a sphenic number, since it is the product of 3 distinct primes.

19420638 is an admirable number.

It is a super-2 number, since 2×19420638² = 754322360654088, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 19420599 and 19420608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19420637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1618381 + ... + 1618392.

It is an arithmetic number, because the mean of its divisors is an integer number (4855161).

Almost surely, 2^19420638 is an apocalyptic number.

19420638 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19420638 is a wasteful number, since it uses less digits than its factorization.

19420638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3236778.

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 19420638 is about 4406.8852946270. The cubic root of 19420638 is about 268.7949866642.

The spelling of 19420638 in words is "nineteen million, four hundred twenty thousand, six hundred thirty-eight".