40397720 has 32 divisors (see below), whose sum is σ = 99159120. Its totient is φ = 14689920.

The previous prime is 40397719. The next prime is 40397737. The reversal of 40397720 is 2779304.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45467 + ... + 46346.

Almost surely, 2^40397720 is an apocalyptic number.

40397720 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

40397720 is an abundant number, since it is smaller than the sum of its proper divisors (58761400).

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

40397720 is a wasteful number, since it uses less digits than its factorization.

40397720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91835 (or 91831 counting only the distinct ones).

The product of its (nonzero) digits is 10584, while the sum is 32.

The square root of 40397720 is about 6355.9200750167. The cubic root of 40397720 is about 343.1249392559.

The spelling of 40397720 in words is "forty million, three hundred ninety-seven thousand, seven hundred twenty".