40655391 has 16 divisors (see below), whose sum is σ = 62366208. Its totient is φ = 23076000.

The previous prime is 40655387. The next prime is 40655413. The reversal of 40655391 is 19355604.

It is a happy number.

It is not a de Polignac number, because 40655391 - 2² = 40655387 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40655491) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3240 + ... + 9581.

It is an arithmetic number, because the mean of its divisors is an integer number (3897888).

Almost surely, 2^40655391 is an apocalyptic number.

40655391 is a deficient number, since it is larger than the sum of its proper divisors (21710817).

40655391 is a wasteful number, since it uses less digits than its factorization.

40655391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12982.

The product of its (nonzero) digits is 16200, while the sum is 33.

The square root of 40655391 is about 6376.1580124711. The cubic root of 40655391 is about 343.8529178998.

The spelling of 40655391 in words is "forty million, six hundred fifty-five thousand, three hundred ninety-one".