20749219 has 4 divisors (see below), whose sum is σ = 20763144. Its totient is φ = 20735296.

The previous prime is 20749213. The next prime is 20749229. The reversal of 20749219 is 91294702.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20749219 - 2⁵ = 20749187 is a prime.

It is a super-2 number, since 2×20749219² = 861060178219922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20749213) 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, 4417 + ... + 7810.

It is an arithmetic number, because the mean of its divisors is an integer number (5190786).

Almost surely, 2^20749219 is an apocalyptic number.

20749219 is a deficient number, since it is larger than the sum of its proper divisors (13925).

20749219 is a wasteful number, since it uses less digits than its factorization.

20749219 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13924.

The product of its (nonzero) digits is 9072, while the sum is 34.

The square root of 20749219 is about 4555.1310628784. The cubic root of 20749219 is about 274.7897853548.

The spelling of 20749219 in words is "twenty million, seven hundred forty-nine thousand, two hundred nineteen".