1217976128 has 14 divisors (see below), whose sum is σ = 2416921506. Its totient is φ = 608988032.

The previous prime is 1217976127. The next prime is 1217976139. The reversal of 1217976128 is 8216797121.

It can be written as a sum of positive squares in only one way, i.e., 1018375744 + 199600384 = 31912^2 + 14128^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1217976121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9515375 + ... + 9515502.

Almost surely, 2^1217976128 is an apocalyptic number.

It is an amenable number.

1217976128 is a deficient number, since it is larger than the sum of its proper divisors (1198945378).

1217976128 is an equidigital number, since it uses as much as digits as its factorization.

1217976128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19030889 (or 19030879 counting only the distinct ones).

The product of its digits is 84672, while the sum is 44.

The square root of 1217976128 is about 34899.5147244199. The cubic root of 1217976128 is about 1067.9385377059.

The spelling of 1217976128 in words is "one billion, two hundred seventeen million, nine hundred seventy-six thousand, one hundred twenty-eight".