21398033406 has 8 divisors (see below), whose sum is σ = 42796066824. Its totient is φ = 7132677800.

The previous prime is 21398033381. The next prime is 21398033407. The reversal of 21398033406 is 60433089312.

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

21398033406 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21398033407) 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, 1783169445 + ... + 1783169456.

It is an arithmetic number, because the mean of its divisors is an integer number (5349508353).

Almost surely, 2^21398033406 is an apocalyptic number.

21398033406 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21398033406 is a wasteful number, since it uses less digits than its factorization.

21398033406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3566338906.

The product of its (nonzero) digits is 93312, while the sum is 39.

The spelling of 21398033406 in words is "twenty-one billion, three hundred ninety-eight million, thirty-three thousand, four hundred six".