1228308731 has 12 divisors (see below), whose sum is σ = 1348295688. Its totient is φ = 1118280384.

The previous prime is 1228308727. The next prime is 1228308779. The reversal of 1228308731 is 1378038221.

It is not a de Polignac number, because 1228308731 - 2² = 1228308727 is a prime.

It is a super-2 number, since 2×1228308731² = 3017484677301660722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1228308691 and 1228308700.

It is not an unprimeable number, because it can be changed into a prime (1228308931) 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, 37445 + ... + 62118.

It is an arithmetic number, because the mean of its divisors is an integer number (112357974).

Almost surely, 2^1228308731 is an apocalyptic number.

1228308731 is a deficient number, since it is larger than the sum of its proper divisors (119986957).

1228308731 is an equidigital number, since it uses as much as digits as its factorization.

1228308731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99662 (or 99649 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 1228308731 is about 35047.2357112512. The cubic root of 1228308731 is about 1070.9499616710.

The spelling of 1228308731 in words is "one billion, two hundred twenty-eight million, three hundred eight thousand, seven hundred thirty-one".