1220978131 has 4 divisors (see below), whose sum is σ = 1292800392. Its totient is φ = 1149155872.

The previous prime is 1220978123. The next prime is 1220978137. The reversal of 1220978131 is 1318790221.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1220978131 - 2³ = 1220978123 is a prime.

It is a super-2 number, since 2×1220978131² = 2981575192760506322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1220978137) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35911105 + ... + 35911138.

It is an arithmetic number, because the mean of its divisors is an integer number (323200098).

Almost surely, 2^1220978131 is an apocalyptic number.

1220978131 is a deficient number, since it is larger than the sum of its proper divisors (71822261).

1220978131 is an equidigital number, since it uses as much as digits as its factorization.

1220978131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71822260.

The product of its (nonzero) digits is 6048, while the sum is 34.

The square root of 1220978131 is about 34942.4974923087. The cubic root of 1220978131 is about 1068.8152172689.

The spelling of 1220978131 in words is "one billion, two hundred twenty million, nine hundred seventy-eight thousand, one hundred thirty-one".