21145494 has 8 divisors (see below), whose sum is σ = 42291000. Its totient is φ = 7048496.

The previous prime is 21145489. The next prime is 21145511. The reversal of 21145494 is 49454112.

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

21145494 is an admirable number.

It is a congruent number.

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, 1762119 + ... + 1762130.

It is an arithmetic number, because the mean of its divisors is an integer number (5286375).

Almost surely, 2^21145494 is an apocalyptic number.

21145494 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.

21145494 is a wasteful number, since it uses less digits than its factorization.

21145494 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3524254.

The product of its digits is 5760, while the sum is 30.

The square root of 21145494 is about 4598.4229905480. The cubic root of 21145494 is about 276.5281056465.

The spelling of 21145494 in words is "twenty-one million, one hundred forty-five thousand, four hundred ninety-four".