1223720131 has 2 divisors, whose sum is σ = 1223720132. Its totient is φ = 1223720130.

The previous prime is 1223720119. The next prime is 1223720143. The reversal of 1223720131 is 1310273221.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (1223720119) and next prime (1223720143).

It is an emirp because it is prime and its reverse (1310273221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1223720131 - 2²¹ = 1221622979 is a prime.

It is a super-2 number, since 2×1223720131² = 2994981918029314322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1223720431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 611860065 + 611860066.

It is an arithmetic number, because the mean of its divisors is an integer number (611860066).

Almost surely, 2^1223720131 is an apocalyptic number.

1223720131 is a deficient number, since it is larger than the sum of its proper divisors (1).

1223720131 is an equidigital number, since it uses as much as digits as its factorization.

1223720131 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 504, while the sum is 22.

The square root of 1223720131 is about 34981.7113789477. The cubic root of 1223720131 is about 1069.6147129430.

Adding to 1223720131 its reverse (1310273221), we get a palindrome (2533993352).

The spelling of 1223720131 in words is "one billion, two hundred twenty-three million, seven hundred twenty thousand, one hundred thirty-one".