39745440 has 144 divisors (see below), whose sum is σ = 155046528. Its totient is φ = 9082368.

The previous prime is 39745429. The next prime is 39745477. The reversal of 39745440 is 4454793.

It is a tau number, because it is divible by the number of its divisors (144).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 39745395 and 39745404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8109 + ... + 12051.

It is an arithmetic number, because the mean of its divisors is an integer number (1076712).

Almost surely, 2^39745440 is an apocalyptic number.

39745440 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 39745440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77523264).

39745440 is an abundant number, since it is smaller than the sum of its proper divisors (115301088).

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

39745440 is a wasteful number, since it uses less digits than its factorization.

39745440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3971 (or 3960 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 36.

The square root of 39745440 is about 6304.3984645642. The cubic root of 39745440 is about 341.2681590788.

The spelling of 39745440 in words is "thirty-nine million, seven hundred forty-five thousand, four hundred forty".