21120073 has 8 divisors (see below), whose sum is σ = 22886528. Its totient is φ = 19373904.

The previous prime is 21120067. The next prime is 21120079. The reversal of 21120073 is 37002112.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21120067) and next prime (21120079).

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

It is a cyclic number.

It is not a de Polignac number, because 21120073 - 2⁵ = 21120041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21120079) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2865 + ... + 7102.

It is an arithmetic number, because the mean of its divisors is an integer number (2860816).

Almost surely, 2^21120073 is an apocalyptic number.

It is an amenable number.

21120073 is a deficient number, since it is larger than the sum of its proper divisors (1766455).

21120073 is a wasteful number, since it uses less digits than its factorization.

21120073 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10143.

The product of its (nonzero) digits is 84, while the sum is 16.

The square root of 21120073 is about 4595.6580595166. The cubic root of 21120073 is about 276.4172476729.

Adding to 21120073 its reverse (37002112), we get a palindrome (58122185).

The spelling of 21120073 in words is "twenty-one million, one hundred twenty thousand, seventy-three".