1640121 has 8 divisors (see below), whose sum is σ = 2499264. Its totient is φ = 937200.

The previous prime is 1640083. The next prime is 1640131. The reversal of 1640121 is 1210461.

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

It is not a de Polignac number, because 1640121 - 2⁶ = 1640057 is a prime.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 1640121.

It is not an unprimeable number, because it can be changed into a prime (1640131) 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, 39030 + ... + 39071.

It is an arithmetic number, because the mean of its divisors is an integer number (312408).

2^1640121 is an apocalyptic number.

It is an amenable number.

1640121 is a deficient number, since it is larger than the sum of its proper divisors (859143).

1640121 is an equidigital number, since it uses as much as digits as its factorization.

1640121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78111.

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 1640121 is about 1280.6720891782. The cubic root of 1640121 is about 117.9302709744.

Adding to 1640121 its reverse (1210461), we get a palindrome (2850582).

The spelling of 1640121 in words is "one million, six hundred forty thousand, one hundred twenty-one".