20740740 has 24 divisors (see below), whose sum is σ = 58074240. Its totient is φ = 5530848.

The previous prime is 20740729. The next prime is 20740747. The reversal of 20740740 is 4704702.

20740740 is a modest number, since divided by 740740 gives 20 as remainder.

It is a self number, because there is not a number n which added to its sum of digits gives 20740740.

It is not an unprimeable number, because it can be changed into a prime (20740747) 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, 172780 + ... + 172899.

It is an arithmetic number, because the mean of its divisors is an integer number (2419760).

Almost surely, 2^20740740 is an apocalyptic number.

20740740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20740740 is an abundant number, since it is smaller than the sum of its proper divisors (37333500).

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

20740740 is a wasteful number, since it uses less digits than its factorization.

20740740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 345691 (or 345689 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 24.

The square root of 20740740 is about 4554.2002591015. The cubic root of 20740740 is about 274.7523500497.

The spelling of 20740740 in words is "twenty million, seven hundred forty thousand, seven hundred forty".