20970240 has 144 divisors (see below), whose sum is σ = 69070848. Its totient is φ = 5419008.

The previous prime is 20970223. The next prime is 20970247. The reversal of 20970240 is 4207902.

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

It is a self number, because there is not a number n which added to its sum of digits gives 20970240.

It is not an unprimeable number, because it can be changed into a prime (20970247) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 165057 + ... + 165183.

Almost surely, 2^20970240 is an apocalyptic number.

20970240 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 20970240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34535424).

20970240 is an abundant number, since it is smaller than the sum of its proper divisors (48100608).

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

20970240 is a wasteful number, since it uses less digits than its factorization.

20970240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 194 (or 180 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 20970240 is about 4579.3274615384. The cubic root of 20970240 is about 275.7620297029.

The spelling of 20970240 in words is "twenty million, nine hundred seventy thousand, two hundred forty".