20767720 has 16 divisors (see below), whose sum is σ = 46727460. Its totient is φ = 8307072.

The previous prime is 20767717. The next prime is 20767723. The reversal of 20767720 is 2776702.

It is an interprime number because it is at equal distance from previous prime (20767717) and next prime (20767723).

It can be written as a sum of positive squares in 2 ways, for example, as 16695396 + 4072324 = 4086^2 + 2018^2 .

It is not an unprimeable number, because it can be changed into a prime (20767723) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 259557 + ... + 259636.

Almost surely, 2^20767720 is an apocalyptic number.

20767720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20767720 is an abundant number, since it is smaller than the sum of its proper divisors (25959740).

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

20767720 is a wasteful number, since it uses less digits than its factorization.

20767720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 519204 (or 519200 counting only the distinct ones).

The product of its (nonzero) digits is 8232, while the sum is 31.

The square root of 20767720 is about 4557.1613971858. The cubic root of 20767720 is about 274.8714330152.

The spelling of 20767720 in words is "twenty million, seven hundred sixty-seven thousand, seven hundred twenty".