20879040 has 224 divisors, whose sum is σ = 81930240. Its totient is φ = 4386816.

The previous prime is 20879039. The next prime is 20879057. The reversal of 20879040 is 4097802.

It is a tau number, because it is divible by the number of its divisors (224).

It is a super-2 number, since 2×20879040² = 871868622643200, 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 = 20878989 and 20879007.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 87241 + ... + 87479.

It is an arithmetic number, because the mean of its divisors is an integer number (365760).

Almost surely, 2^20879040 is an apocalyptic number.

20879040 is a gapful number since it is divisible by the number (20) 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 20879040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40965120).

20879040 is an abundant number, since it is smaller than the sum of its proper divisors (61051200).

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

20879040 is a wasteful number, since it uses less digits than its factorization.

20879040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 279 (or 269 counting only the distinct ones).

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

The square root of 20879040 is about 4569.3588171646. The cubic root of 20879040 is about 275.3616838793.

The spelling of 20879040 in words is "twenty million, eight hundred seventy-nine thousand, forty".