21910405898 has 8 divisors (see below), whose sum is σ = 32868790308. Its totient is φ = 10954142464.

The previous prime is 21910405879. The next prime is 21910405901. The reversal of 21910405898 is 89850401912.

It can be written as a sum of positive squares in 2 ways, for example, as 21621643849 + 288762049 = 147043^2 + 16993^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21910405898² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 504161 + ... + 545892.

Almost surely, 2^21910405898 is an apocalyptic number.

21910405898 is a deficient number, since it is larger than the sum of its proper divisors (10958384410).

21910405898 is a wasteful number, since it uses less digits than its factorization.

21910405898 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1060488.

The product of its (nonzero) digits is 207360, while the sum is 47.

The spelling of 21910405898 in words is "twenty-one billion, nine hundred ten million, four hundred five thousand, eight hundred ninety-eight".