1228642690 has 16 divisors (see below), whose sum is σ = 2412607680. Its totient is φ = 446779120.

The previous prime is 1228642673. The next prime is 1228642699. The reversal of 1228642690 is 962468221.

It is a super-2 number, since 2×1228642690² = 3019125719380872200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1228642699) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5584630 + ... + 5584849.

It is an arithmetic number, because the mean of its divisors is an integer number (150787980).

Almost surely, 2^1228642690 is an apocalyptic number.

1228642690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1228642690 is a deficient number, since it is larger than the sum of its proper divisors (1183964990).

1228642690 is a wasteful number, since it uses less digits than its factorization.

1228642690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11169497.

The product of its (nonzero) digits is 82944, while the sum is 40.

The square root of 1228642690 is about 35051.9998002967. Note that the first 3 decimals coincide. The cubic root of 1228642690 is about 1071.0470113678.

The spelling of 1228642690 in words is "one billion, two hundred twenty-eight million, six hundred forty-two thousand, six hundred ninety".