1213615491 has 16 divisors (see below), whose sum is σ = 1765843200. Its totient is φ = 735281120.

The previous prime is 1213615489. The next prime is 1213615537. The reversal of 1213615491 is 1945163121.

It is a cyclic number.

It is not a de Polignac number, because 1213615491 - 2¹ = 1213615489 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (1213615691) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 180610 + ... + 187208.

It is an arithmetic number, because the mean of its divisors is an integer number (110365200).

Almost surely, 2^1213615491 is an apocalyptic number.

1213615491 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1213615491 is a deficient number, since it is larger than the sum of its proper divisors (552227709).

1213615491 is a wasteful number, since it uses less digits than its factorization.

1213615491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12186.

The product of its digits is 6480, while the sum is 33.

The square root of 1213615491 is about 34836.9845279410. The cubic root of 1213615491 is about 1066.6625244739.

The spelling of 1213615491 in words is "one billion, two hundred thirteen million, six hundred fifteen thousand, four hundred ninety-one".