20406624 has 48 divisors (see below), whose sum is σ = 61221888. Its totient is φ = 5830272.

The previous prime is 20406611. The next prime is 20406641. The reversal of 20406624 is 42660402.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a junction number, because it is equal to n+sod(n) for n = 20406594 and 20406603.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 14512 + ... + 15855.

It is an arithmetic number, because the mean of its divisors is an integer number (1275456).

Almost surely, 2^20406624 is an apocalyptic number.

20406624 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20406624 is an abundant number, since it is smaller than the sum of its proper divisors (40815264).

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

20406624 is a wasteful number, since it uses less digits than its factorization.

20406624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30387 (or 30379 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

The square root of 20406624 is about 4517.3691458636. The cubic root of 20406624 is about 273.2690125604.

The spelling of 20406624 in words is "twenty million, four hundred six thousand, six hundred twenty-four".