39913965 has 144 divisors (see below), whose sum is σ = 93195648. Its totient is φ = 15956352.

The previous prime is 39913963. The next prime is 39913967. The reversal of 39913965 is 56931993.

It is an interprime number because it is at equal distance from previous prime (39913963) and next prime (39913967).

It is not a de Polignac number, because 39913965 - 2¹ = 39913963 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 39913965.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39913961) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 2100726 + ... + 2100744.

It is an arithmetic number, because the mean of its divisors is an integer number (647192).

Almost surely, 2^39913965 is an apocalyptic number.

39913965 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

39913965 is an abundant number, since it is smaller than the sum of its proper divisors (53281683).

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

39913965 is a wasteful number, since it uses less digits than its factorization.

39913965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78 (or 47 counting only the distinct ones).

The product of its digits is 196830, while the sum is 45.

The square root of 39913965 is about 6317.7499950536. The cubic root of 39913965 is about 341.7498170285.

The spelling of 39913965 in words is "thirty-nine million, nine hundred thirteen thousand, nine hundred sixty-five".