22721031 has 12 divisors (see below), whose sum is σ = 33269808. Its totient is φ = 14939424.

The previous prime is 22721029. The next prime is 22721051. The reversal of 22721031 is 13012722.

It is not a de Polignac number, because 22721031 - 2¹ = 22721029 is a prime.

It is a super-2 number, since 2×22721031² = 1032490499405922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 22720995 and 22721013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22721021) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16635 + ... + 17948.

It is an arithmetic number, because the mean of its divisors is an integer number (2772484).

Almost surely, 2^22721031 is an apocalyptic number.

22721031 is a deficient number, since it is larger than the sum of its proper divisors (10548777).

22721031 is a wasteful number, since it uses less digits than its factorization.

22721031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34662 (or 34659 counting only the distinct ones).

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

The square root of 22721031 is about 4766.6582633959. The cubic root of 22721031 is about 283.2322341338.

Adding to 22721031 its reverse (13012722), we get a palindrome (35733753).

It can be divided in two parts, 2272 and 1031, that multiplied together give a palindrome (2342432).

The spelling of 22721031 in words is "twenty-two million, seven hundred twenty-one thousand, thirty-one".