21019426 has 8 divisors (see below), whose sum is σ = 32546304. Its totient is φ = 10170660.

The previous prime is 21019409. The next prime is 21019459. The reversal of 21019426 is 62491012.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21019426.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 169450 + ... + 169573.

It is an arithmetic number, because the mean of its divisors is an integer number (4068288).

Almost surely, 2^21019426 is an apocalyptic number.

21019426 is a deficient number, since it is larger than the sum of its proper divisors (11526878).

21019426 is a wasteful number, since it uses less digits than its factorization.

21019426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 339056.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 21019426 is about 4584.6947553790. The cubic root of 21019426 is about 275.9774626280.

The spelling of 21019426 in words is "twenty-one million, nineteen thousand, four hundred twenty-six".