40139213 has 2 divisors, whose sum is σ = 40139214. Its totient is φ = 40139212.

The previous prime is 40139207. The next prime is 40139243. The reversal of 40139213 is 31293104.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24631369 + 15507844 = 4963^2 + 3938^2 .

It is a cyclic number.

It is not a de Polignac number, because 40139213 - 2⁶ = 40139149 is a prime.

It is a super-2 number, since 2×40139213² = 3222312840518738, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40139243) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20069606 + 20069607.

It is an arithmetic number, because the mean of its divisors is an integer number (20069607).

Almost surely, 2^40139213 is an apocalyptic number.

It is an amenable number.

40139213 is a deficient number, since it is larger than the sum of its proper divisors (1).

40139213 is an equidigital number, since it uses as much as digits as its factorization.

40139213 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 40139213 is about 6335.5515150617. The cubic root of 40139213 is about 342.3914814176.

The spelling of 40139213 in words is "forty million, one hundred thirty-nine thousand, two hundred thirteen".