21125073 has 8 divisors (see below), whose sum is σ = 28188000. Its totient is φ = 14072768.

The previous prime is 21125057. The next prime is 21125087. The reversal of 21125073 is 37052112.

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 21125073 - 2⁴ = 21125057 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21125003) 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, 6478 + ... + 9176.

It is an arithmetic number, because the mean of its divisors is an integer number (3523500).

Almost surely, 2^21125073 is an apocalyptic number.

It is an amenable number.

21125073 is a deficient number, since it is larger than the sum of its proper divisors (7062927).

21125073 is a wasteful number, since it uses less digits than its factorization.

21125073 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5311.

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

The square root of 21125073 is about 4596.2020190588. The cubic root of 21125073 is about 276.4390591061.

Adding to 21125073 its reverse (37052112), we get a palindrome (58177185).

The spelling of 21125073 in words is "twenty-one million, one hundred twenty-five thousand, seventy-three".