20015940 has 48 divisors (see below), whose sum is σ = 64052352. Its totient is φ = 4574976.

The previous prime is 20015923. The next prime is 20015977. The reversal of 20015940 is 4951002.

It is a Harshad number since it is a multiple of its sum of digits (21).

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 15 ways as a sum of consecutive naturals, for example, 23409 + ... + 24248.

It is an arithmetic number, because the mean of its divisors is an integer number (1334424).

Almost surely, 2^20015940 is an apocalyptic number.

20015940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20015940 is an abundant number, since it is smaller than the sum of its proper divisors (44036412).

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

20015940 is a wasteful number, since it uses less digits than its factorization.

20015940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47676 (or 47674 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 20015940 is about 4473.9177462265. The cubic root of 20015940 is about 271.5138555380.

Adding to 20015940 its reverse (4951002), we get a palindrome (24966942).

The spelling of 20015940 in words is "twenty million, fifteen thousand, nine hundred forty".