144161721 has 64 divisors (see below), whose sum is σ = 249984000. Its totient is φ = 81181440.

The previous prime is 144161681. The next prime is 144161747. The reversal of 144161721 is 127161441.

144161721 is a `hidden beast` number, since 1 + 4 + 41 + 617 + 2 + 1 = 666.

It is not a de Polignac number, because 144161721 - 2²¹ = 142064569 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (144161791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 332721 + ... + 333153.

It is an arithmetic number, because the mean of its divisors is an integer number (3906000).

Almost surely, 2^144161721 is an apocalyptic number.

144161721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

144161721 is a deficient number, since it is larger than the sum of its proper divisors (105822279).

144161721 is a wasteful number, since it uses less digits than its factorization.

144161721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 531 (or 525 counting only the distinct ones).

The product of its digits is 1344, while the sum is 27.

The square root of 144161721 is about 12006.7364841575. The cubic root of 144161721 is about 524.3444225250.

The spelling of 144161721 in words is "one hundred forty-four million, one hundred sixty-one thousand, seven hundred twenty-one".