140240921 has 2 divisors, whose sum is σ = 140240922. Its totient is φ = 140240920.

The previous prime is 140240887. The next prime is 140240929. The reversal of 140240921 is 129042041.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 96746896 + 43494025 = 9836^2 + 6595^2 .

It is an emirp because it is prime and its reverse (129042041) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-140240921 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (140240929) 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 as a sum of consecutive naturals, namely, 70120460 + 70120461.

It is an arithmetic number, because the mean of its divisors is an integer number (70120461).

Almost surely, 2^140240921 is an apocalyptic number.

It is an amenable number.

140240921 is a deficient number, since it is larger than the sum of its proper divisors (1).

140240921 is an equidigital number, since it uses as much as digits as its factorization.

140240921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 140240921 is about 11842.3359604429. The cubic root of 140240921 is about 519.5470920821.

Adding to 140240921 its reverse (129042041), we get a palindrome (269282962).

The spelling of 140240921 in words is "one hundred forty million, two hundred forty thousand, nine hundred twenty-one".