20724970 has 16 divisors (see below), whose sum is σ = 42634368. Its totient is φ = 7105680.

The previous prime is 20724959. The next prime is 20724973. The reversal of 20724970 is 7942702.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (20724973) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 147966 + ... + 148105.

It is an arithmetic number, because the mean of its divisors is an integer number (2664648).

Almost surely, 2^20724970 is an apocalyptic number.

20724970 is an abundant number, since it is smaller than the sum of its proper divisors (21909398).

20724970 is a wasteful number, since it uses less digits than its factorization.

20724970 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 296085.

The product of its (nonzero) digits is 7056, while the sum is 31.

The square root of 20724970 is about 4552.4685611215. The cubic root of 20724970 is about 274.6826973892.

The spelling of 20724970 in words is "twenty million, seven hundred twenty-four thousand, nine hundred seventy".