20219723 has 4 divisors (see below), whose sum is σ = 20766240. Its totient is φ = 19673208.

The previous prime is 20219701. The next prime is 20219741. The reversal of 20219723 is 32791202.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32791202 = 2 ⋅16395601.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20219723 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20219692 and 20219701.

It is not an unprimeable number, because it can be changed into a prime (20212723) 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, 273203 + ... + 273276.

It is an arithmetic number, because the mean of its divisors is an integer number (5191560).

Almost surely, 2^20219723 is an apocalyptic number.

20219723 is a deficient number, since it is larger than the sum of its proper divisors (546517).

20219723 is an equidigital number, since it uses as much as digits as its factorization.

20219723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 546516.

The product of its (nonzero) digits is 1512, while the sum is 26.

The square root of 20219723 is about 4496.6346304764. The cubic root of 20219723 is about 272.4321768193.

The spelling of 20219723 in words is "twenty million, two hundred nineteen thousand, seven hundred twenty-three".