1291921154 has 16 divisors (see below), whose sum is σ = 2099595168. Its totient is φ = 593823552.

The previous prime is 1291921153. The next prime is 1291921159. The reversal of 1291921154 is 4511291921.

It is not an unprimeable number, because it can be changed into a prime (1291921151) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 440372 + ... + 443295.

It is an arithmetic number, because the mean of its divisors is an integer number (131224698).

Almost surely, 2^1291921154 is an apocalyptic number.

1291921154 is a deficient number, since it is larger than the sum of its proper divisors (807674014).

1291921154 is a wasteful number, since it uses less digits than its factorization.

1291921154 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 883729.

The product of its digits is 6480, while the sum is 35.

The square root of 1291921154 is about 35943.3047172905. The cubic root of 1291921154 is about 1089.1273643022.

The spelling of 1291921154 in words is "one billion, two hundred ninety-one million, nine hundred twenty-one thousand, one hundred fifty-four".