21152073 has 12 divisors (see below), whose sum is σ = 29766768. Its totient is φ = 13358520.

The previous prime is 21152069. The next prime is 21152077. The reversal of 21152073 is 37025112.

It is an interprime number because it is at equal distance from previous prime (21152069) and next prime (21152077).

It is not a de Polignac number, because 21152073 - 2² = 21152069 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21152077) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8683 + ... + 10848.

It is an arithmetic number, because the mean of its divisors is an integer number (2480564).

Almost surely, 2^21152073 is an apocalyptic number.

It is an amenable number.

21152073 is a deficient number, since it is larger than the sum of its proper divisors (8614695).

21152073 is a wasteful number, since it uses less digits than its factorization.

21152073 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19572 (or 19553 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 21152073 is about 4599.1382888537. The cubic root of 21152073 is about 276.5567814132.

Adding to 21152073 its reverse (37025112), we get a palindrome (58177185).

The spelling of 21152073 in words is "twenty-one million, one hundred fifty-two thousand, seventy-three".