21889560949 has 2 divisors, whose sum is σ = 21889560950. Its totient is φ = 21889560948.

The previous prime is 21889560941. The next prime is 21889560967. The reversal of 21889560949 is 94906598812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11359722724 + 10529838225 = 106582^2 + 102615^2 .

It is a cyclic number.

It is not a de Polignac number, because 21889560949 - 2³ = 21889560941 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21889560941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10944780474 + 10944780475.

It is an arithmetic number, because the mean of its divisors is an integer number (10944780475).

Almost surely, 2^21889560949 is an apocalyptic number.

It is an amenable number.

21889560949 is a deficient number, since it is larger than the sum of its proper divisors (1).

21889560949 is an equidigital number, since it uses as much as digits as its factorization.

21889560949 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11197440, while the sum is 61.

The spelling of 21889560949 in words is "twenty-one billion, eight hundred eighty-nine million, five hundred sixty thousand, nine hundred forty-nine".