21140073 has 6 divisors (see below), whose sum is σ = 30535674. Its totient is φ = 14093376.

The previous prime is 21140069. The next prime is 21140089. The reversal of 21140073 is 37004112.

It can be written as a sum of positive squares in only one way, i.e., 16064064 + 5076009 = 4008^2 + 2253^2 .

It is not a de Polignac number, because 21140073 - 2² = 21140069 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21140003) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1174440 + ... + 1174457.

It is an arithmetic number, because the mean of its divisors is an integer number (5089279).

Almost surely, 2^21140073 is an apocalyptic number.

It is an amenable number.

21140073 is a deficient number, since it is larger than the sum of its proper divisors (9395601).

21140073 is a wasteful number, since it uses less digits than its factorization.

21140073 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2348903 (or 2348900 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 21140073 is about 4597.8335115574. The cubic root of 21140073 is about 276.5044727631.

Adding to 21140073 its reverse (37004112), we get a palindrome (58144185).

The spelling of 21140073 in words is "twenty-one million, one hundred forty thousand, seventy-three".