20870940 has 24 divisors (see below), whose sum is σ = 58438800. Its totient is φ = 5565568.

The previous prime is 20870939. The next prime is 20871001. The reversal of 20870940 is 4907802.

It is a super-2 number, since 2×20870940² = 871192272967200, which contains 22 as substring.

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 = 20870898 and 20870907.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 173865 + ... + 173984.

It is an arithmetic number, because the mean of its divisors is an integer number (2434950).

Almost surely, 2^20870940 is an apocalyptic number.

20870940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20870940 is an abundant number, since it is smaller than the sum of its proper divisors (37567860).

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

20870940 is a wasteful number, since it uses less digits than its factorization.

20870940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347861 (or 347859 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 20870940 is about 4568.4723923868. The cubic root of 20870940 is about 275.3260705221.

The spelling of 20870940 in words is "twenty million, eight hundred seventy thousand, nine hundred forty".