20705538 has 32 divisors (see below), whose sum is σ = 48297600. Its totient is φ = 5915280.

The previous prime is 20705537. The next prime is 20705539. The reversal of 20705538 is 83550702.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20705537) and next prime (20705539).

It is a super-4 number, since 4×20705538⁴ (a number of 30 digits) contains 4444 as substring.

It is not an unprimeable number, because it can be changed into a prime (20705537) 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, 2973 + ... + 7088.

It is an arithmetic number, because the mean of its divisors is an integer number (1509300).

Almost surely, 2^20705538 is an apocalyptic number.

20705538 is an abundant number, since it is smaller than the sum of its proper divisors (27592062).

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

20705538 is a wasteful number, since it uses less digits than its factorization.

20705538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10087 (or 10073 counting only the distinct ones).

The product of its (nonzero) digits is 8400, while the sum is 30.

The square root of 20705538 is about 4550.3338339071. Note that the first 3 decimals coincide. The cubic root of 20705538 is about 274.5968218606.

The spelling of 20705538 in words is "twenty million, seven hundred five thousand, five hundred thirty-eight".