1221122987 has 32 divisors (see below), whose sum is σ = 1464883200. Its totient is φ = 996323328.

The previous prime is 1221122963. The next prime is 1221122993. The reversal of 1221122987 is 7892211221.

It is not a de Polignac number, because 1221122987 - 2²² = 1216928683 is a prime.

It is a super-2 number, since 2×1221122987² = 2982282698759604338, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221122927) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2116043 + ... + 2116619.

It is an arithmetic number, because the mean of its divisors is an integer number (45777600).

Almost surely, 2^1221122987 is an apocalyptic number.

1221122987 is a deficient number, since it is larger than the sum of its proper divisors (243760213).

1221122987 is an equidigital number, since it uses as much as digits as its factorization.

1221122987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 795.

The product of its digits is 8064, while the sum is 35.

The square root of 1221122987 is about 34944.5702076875. The cubic root of 1221122987 is about 1068.8574834299.

The spelling of 1221122987 in words is "one billion, two hundred twenty-one million, one hundred twenty-two thousand, nine hundred eighty-seven".