40297720 has 32 divisors (see below), whose sum is σ = 91559520. Its totient is φ = 15960960.

The previous prime is 40297709. The next prime is 40297723. The reversal of 40297720 is 2779204.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40297723) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 771 + ... + 9010.

It is an arithmetic number, because the mean of its divisors is an integer number (2861235).

Almost surely, 2^40297720 is an apocalyptic number.

40297720 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

40297720 is an abundant number, since it is smaller than the sum of its proper divisors (51261800).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

40297720 is a wasteful number, since it uses less digits than its factorization.

40297720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9895 (or 9891 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 31.

The square root of 40297720 is about 6348.0485190332. The cubic root of 40297720 is about 342.8415829579.

The spelling of 40297720 in words is "forty million, two hundred ninety-seven thousand, seven hundred twenty".