40646551 has 4 divisors (see below), whose sum is σ = 44341704. Its totient is φ = 36951400.

The previous prime is 40646533. The next prime is 40646561. The reversal of 40646551 is 15564604.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 40646551 - 2¹⁹ = 40122263 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40646531) 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, 1847560 + ... + 1847581.

It is an arithmetic number, because the mean of its divisors is an integer number (11085426).

Almost surely, 2^40646551 is an apocalyptic number.

40646551 is a deficient number, since it is larger than the sum of its proper divisors (3695153).

40646551 is a wasteful number, since it uses less digits than its factorization.

40646551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3695152.

The product of its (nonzero) digits is 14400, while the sum is 31.

The square root of 40646551 is about 6375.4647673719. The cubic root of 40646551 is about 343.8279939389.

The spelling of 40646551 in words is "forty million, six hundred forty-six thousand, five hundred fifty-one".