39420840 has 64 divisors (see below), whose sum is σ = 122088960. Its totient is φ = 10172160.

The previous prime is 39420811. The next prime is 39420847. The reversal of 39420840 is 4802493.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 39420798 and 39420807.

It is not an unprimeable number, because it can be changed into a prime (39420847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1579 + ... + 9018.

It is an arithmetic number, because the mean of its divisors is an integer number (1907640).

Almost surely, 2^39420840 is an apocalyptic number.

39420840 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 39420840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (61044480).

39420840 is an abundant number, since it is smaller than the sum of its proper divisors (82668120).

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

39420840 is a wasteful number, since it uses less digits than its factorization.

39420840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10642 (or 10638 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 39420840 is about 6278.6017551681. The cubic root of 39420840 is about 340.3365755856.

The spelling of 39420840 in words is "thirty-nine million, four hundred twenty thousand, eight hundred forty".