15220723 has 6 divisors (see below), whose sum is σ = 17705796. Its totient is φ = 13046292.

The previous prime is 15220703. The next prime is 15220739. The reversal of 15220723 is 32702251.

It is not a de Polignac number, because 15220723 - 2¹⁷ = 15089651 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 15220694 and 15220703.

It is not an unprimeable number, because it can be changed into a prime (15220703) 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, 155265 + ... + 155362.

It is an arithmetic number, because the mean of its divisors is an integer number (2950966).

Almost surely, 2^15220723 is an apocalyptic number.

15220723 is a deficient number, since it is larger than the sum of its proper divisors (2485073).

15220723 is an equidigital number, since it uses as much as digits as its factorization.

15220723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 310641 (or 310634 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 22.

The square root of 15220723 is about 3901.3745013777. The cubic root of 15220723 is about 247.8249881703.

Adding to 15220723 its reverse (32702251), we get a palindrome (47922974).

The spelling of 15220723 in words is "fifteen million, two hundred twenty thousand, seven hundred twenty-three".