40139221 has 4 divisors (see below), whose sum is σ = 40169952. Its totient is φ = 40108492.

The previous prime is 40139213. The next prime is 40139243. The reversal of 40139221 is 12293104.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 40139221 - 2³ = 40139213 is a prime.

It is a super-2 number, since 2×40139221² = 3222314124973682, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 40139192 and 40139201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40139201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13315 + ... + 16048.

It is an arithmetic number, because the mean of its divisors is an integer number (10042488).

Almost surely, 2^40139221 is an apocalyptic number.

It is an amenable number.

40139221 is a deficient number, since it is larger than the sum of its proper divisors (30731).

40139221 is a wasteful number, since it uses less digits than its factorization.

40139221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30730.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 40139221 is about 6335.5521464194. The cubic root of 40139221 is about 342.3915041646.

The spelling of 40139221 in words is "forty million, one hundred thirty-nine thousand, two hundred twenty-one".