21607373 has 4 divisors (see below), whose sum is σ = 22546848. Its totient is φ = 20667900.

The previous prime is 21607367. The next prime is 21607381. The reversal of 21607373 is 37370612.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21607373 - 2⁶ = 21607309 is a prime.

It is a super-2 number, since 2×21607373² = 933757135922258, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21607673) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 469703 + ... + 469748.

It is an arithmetic number, because the mean of its divisors is an integer number (5636712).

Almost surely, 2^21607373 is an apocalyptic number.

21607373 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21607373 is a deficient number, since it is larger than the sum of its proper divisors (939475).

21607373 is an equidigital number, since it uses as much as digits as its factorization.

21607373 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 939474.

The product of its (nonzero) digits is 5292, while the sum is 29.

The square root of 21607373 is about 4648.3731562774. The cubic root of 21607373 is about 278.5270138514.

Adding to 21607373 its reverse (37370612), we get a palindrome (58977985).

The spelling of 21607373 in words is "twenty-one million, six hundred seven thousand, three hundred seventy-three".