1211519971 has 12 divisors (see below), whose sum is σ = 1313212512. Its totient is φ = 1116723024.

The previous prime is 1211519923. The next prime is 1211519989. The reversal of 1211519971 is 1799151121.

It is not a de Polignac number, because 1211519971 - 2⁷ = 1211519843 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a self number, because there is not a number n which added to its sum of digits gives 1211519971.

It is not an unprimeable number, because it can be changed into a prime (1211549971) 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, 31995 + ... + 58708.

It is an arithmetic number, because the mean of its divisors is an integer number (109434376).

Almost surely, 2^1211519971 is an apocalyptic number.

1211519971 is a deficient number, since it is larger than the sum of its proper divisors (101692541).

1211519971 is an equidigital number, since it uses as much as digits as its factorization.

1211519971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90778 (or 90759 counting only the distinct ones).

The product of its digits is 5670, while the sum is 37.

The square root of 1211519971 is about 34806.8954519072. The cubic root of 1211519971 is about 1066.0482441408.

The spelling of 1211519971 in words is "one billion, two hundred eleven million, five hundred nineteen thousand, nine hundred seventy-one".