191220004 has 24 divisors (see below), whose sum is σ = 337668408. Its totient is φ = 94748160.

The previous prime is 191219993. The next prime is 191220019. The reversal of 191220004 is 400022191.

It can be written as a sum of positive squares in 4 ways, for example, as 159971904 + 31248100 = 12648^2 + 5590^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 282114 + ... + 282790.

It is an arithmetic number, because the mean of its divisors is an integer number (14069517).

Almost surely, 2^191220004 is an apocalyptic number.

It is an amenable number.

191220004 is a deficient number, since it is larger than the sum of its proper divisors (146448404).

191220004 is a wasteful number, since it uses less digits than its factorization.

191220004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1215 (or 1213 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 191220004 is about 13828.2321357432. The cubic root of 191220004 is about 576.1175533287.

Adding to 191220004 its reverse (400022191), we get a palindrome (591242195).

The spelling of 191220004 in words is "one hundred ninety-one million, two hundred twenty thousand, four".