20897770 has 16 divisors (see below), whose sum is σ = 37781640. Its totient is φ = 8322304.

The previous prime is 20897761. The next prime is 20897801. The reversal of 20897770 is 7779802.

It can be written as a sum of positive squares in 4 ways, for example, as 14070001 + 6827769 = 3751^2 + 2613^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2155 + ... + 6814.

Almost surely, 2^20897770 is an apocalyptic number.

20897770 is a deficient number, since it is larger than the sum of its proper divisors (16883870).

20897770 is a wasteful number, since it uses less digits than its factorization.

20897770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9209.

The product of its (nonzero) digits is 49392, while the sum is 40.

The square root of 20897770 is about 4571.4078794175. The cubic root of 20897770 is about 275.4439990127.

The spelling of 20897770 in words is "twenty million, eight hundred ninety-seven thousand, seven hundred seventy".