1640252121 has 16 divisors (see below), whose sum is σ = 2304133440. Its totient is φ = 1035037440.

The previous prime is 1640252099. The next prime is 1640252137. The reversal of 1640252121 is 1212520461.

It is not a de Polignac number, because 1640252121 - 2²² = 1636057817 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1640252091 and 1640252100.

It is not an unprimeable number, because it can be changed into a prime (1640259121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55941 + ... + 80061.

It is an arithmetic number, because the mean of its divisors is an integer number (144008340).

Almost surely, 2^1640252121 is an apocalyptic number.

It is an amenable number.

1640252121 is a deficient number, since it is larger than the sum of its proper divisors (663881319).

1640252121 is a wasteful number, since it uses less digits than its factorization.

1640252121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25336.

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 1640252121 is about 40500.0261851767. The cubic root of 1640252121 is about 1179.3341357241.

Adding to 1640252121 its reverse (1212520461), we get a palindrome (2852772582).

The spelling of 1640252121 in words is "one billion, six hundred forty million, two hundred fifty-two thousand, one hundred twenty-one".