21019434 has 32 divisors (see below), whose sum is σ = 45204480. Its totient is φ = 6494832.

The previous prime is 21019409. The next prime is 21019459. The reversal of 21019434 is 43491012.

It is an interprime number because it is at equal distance from previous prime (21019409) and next prime (21019459).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3397 + ... + 7319.

It is an arithmetic number, because the mean of its divisors is an integer number (1412640).

Almost surely, 2^21019434 is an apocalyptic number.

21019434 is an abundant number, since it is smaller than the sum of its proper divisors (24185046).

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

21019434 is a wasteful number, since it uses less digits than its factorization.

21019434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3994.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 21019434 is about 4584.6956278471. The cubic root of 21019434 is about 275.9774976403.

The spelling of 21019434 in words is "twenty-one million, nineteen thousand, four hundred thirty-four".