291954081321 has 128 divisors (see below), whose sum is σ = 519738490880. Its totient is φ = 158471769600.

The previous prime is 291954081311. The next prime is 291954081337. The reversal of 291954081321 is 123180459192.

291954081321 is a `hidden beast` number, since 2 + 9 + 1 + 9 + 540 + 81 + 3 + 21 = 666.

It is not a de Polignac number, because 291954081321 - 2⁶ = 291954081257 is a prime.

It is a super-2 number, since 2×291954081321² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (291954081311) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 95377131 + ... + 95380191.

It is an arithmetic number, because the mean of its divisors is an integer number (4060456960).

Almost surely, 2^291954081321 is an apocalyptic number.

291954081321 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

291954081321 is a deficient number, since it is larger than the sum of its proper divisors (227784409559).

291954081321 is a wasteful number, since it uses less digits than its factorization.

291954081321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3404 (or 3398 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 45.

The spelling of 291954081321 in words is "two hundred ninety-one billion, nine hundred fifty-four million, eighty-one thousand, three hundred twenty-one".