21621682346 has 32 divisors (see below), whose sum is σ = 37086831936. Its totient is φ = 9365328000.

The previous prime is 21621682343. The next prime is 21621682393. The reversal of 21621682346 is 64328612612.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is not an unprimeable number, because it can be changed into a prime (21621682343) 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, 239945 + ... + 317516.

It is an arithmetic number, because the mean of its divisors is an integer number (1158963498).

Almost surely, 2^21621682346 is an apocalyptic number.

21621682346 is a deficient number, since it is larger than the sum of its proper divisors (15465149590).

21621682346 is a wasteful number, since it uses less digits than its factorization.

21621682346 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 557558.

The product of its digits is 165888, while the sum is 41.

The spelling of 21621682346 in words is "twenty-one billion, six hundred twenty-one million, six hundred eighty-two thousand, three hundred forty-six".