140643521 has 2 divisors, whose sum is σ = 140643522. Its totient is φ = 140643520.

The previous prime is 140643487. The next prime is 140643541. The reversal of 140643521 is 125346041.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 134212225 + 6431296 = 11585^2 + 2536^2 .

It is a cyclic number.

It is not a de Polignac number, because 140643521 - 2⁶ = 140643457 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (140643541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 70321760 + 70321761.

It is an arithmetic number, because the mean of its divisors is an integer number (70321761).

Almost surely, 2^140643521 is an apocalyptic number.

It is an amenable number.

140643521 is a deficient number, since it is larger than the sum of its proper divisors (1).

140643521 is an equidigital number, since it uses as much as digits as its factorization.

140643521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 140643521 is about 11859.3221138478. The cubic root of 140643521 is about 520.0437845282.

Adding to 140643521 its reverse (125346041), we get a palindrome (265989562).

The spelling of 140643521 in words is "one hundred forty million, six hundred forty-three thousand, five hundred twenty-one".