20916740 has 24 divisors (see below), whose sum is σ = 47304600. Its totient is φ = 7723008.

The previous prime is 20916713. The next prime is 20916767. The reversal of 20916740 is 4761902.

It is an interprime number because it is at equal distance from previous prime (20916713) and next prime (20916767).

It can be written as a sum of positive squares in 4 ways, for example, as 141376 + 20775364 = 376^2 + 4558^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39965 + ... + 40484.

It is an arithmetic number, because the mean of its divisors is an integer number (1971025).

Almost surely, 2^20916740 is an apocalyptic number.

20916740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20916740 is an abundant number, since it is smaller than the sum of its proper divisors (26387860).

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

20916740 is a wasteful number, since it uses less digits than its factorization.

20916740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80471 (or 80469 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 20916740 is about 4573.4822619094. The cubic root of 20916740 is about 275.5273187864.

The spelling of 20916740 in words is "twenty million, nine hundred sixteen thousand, seven hundred forty".