21459994 has 8 divisors (see below), whose sum is σ = 32256000. Its totient is φ = 10707996.

The previous prime is 21459979. The next prime is 21460003. The reversal of 21459994 is 49995412.

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 21459994.

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, 9754 + ... + 11749.

It is an arithmetic number, because the mean of its divisors is an integer number (4032000).

Almost surely, 2^21459994 is an apocalyptic number.

21459994 is a deficient number, since it is larger than the sum of its proper divisors (10796006).

21459994 is a wasteful number, since it uses less digits than its factorization.

21459994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22004.

The product of its digits is 116640, while the sum is 43.

The square root of 21459994 is about 4632.4932811608. The cubic root of 21459994 is about 277.8923120335.

It can be divided in two parts, 21459 and 994, that multiplied together give a triangular number (21330246 = T₆₅₃₁).

The spelling of 21459994 in words is "twenty-one million, four hundred fifty-nine thousand, nine hundred ninety-four".