1640243121 has 8 divisors (see below), whose sum is σ = 2385808224. Its totient is φ = 994086720.

The previous prime is 1640243069. The next prime is 1640243123. The reversal of 1640243121 is 1213420461.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1640243121 - 2¹³ = 1640234929 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1640243091 and 1640243100.

It is not an unprimeable number, because it can be changed into a prime (1640243123) 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, 24852136 + ... + 24852201.

It is an arithmetic number, because the mean of its divisors is an integer number (298226028).

Almost surely, 2^1640243121 is an apocalyptic number.

1640243121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1640243121 is a deficient number, since it is larger than the sum of its proper divisors (745565103).

1640243121 is a wasteful number, since it uses less digits than its factorization.

1640243121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49704351.

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 1640243121 is about 40499.9150739850. The cubic root of 1640243121 is about 1179.3319787333.

Adding to 1640243121 its reverse (1213420461), we get a palindrome (2853663582).

The spelling of 1640243121 in words is "one billion, six hundred forty million, two hundred forty-three thousand, one hundred twenty-one".