40287791 has 4 divisors (see below), whose sum is σ = 41047992. Its totient is φ = 39527592.

The previous prime is 40287787. The next prime is 40287803. The reversal of 40287791 is 19778204.

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 40287791 - 2² = 40287787 is a prime.

It is a super-2 number, since 2×40287791² = 3246212207319362, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40287701) 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, 380021 + ... + 380126.

It is an arithmetic number, because the mean of its divisors is an integer number (10261998).

Almost surely, 2^40287791 is an apocalyptic number.

40287791 is a deficient number, since it is larger than the sum of its proper divisors (760201).

40287791 is an equidigital number, since it uses as much as digits as its factorization.

40287791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 760200.

The product of its (nonzero) digits is 28224, while the sum is 38.

The square root of 40287791 is about 6347.2664194911. The cubic root of 40287791 is about 342.8134229388.

The spelling of 40287791 in words is "forty million, two hundred eighty-seven thousand, seven hundred ninety-one".