21651405893830 has 8 divisors (see below), whose sum is σ = 38972530608912. Its totient is φ = 8660562357528.

The previous prime is 21651405893827. The next prime is 21651405893891. The reversal of 21651405893830 is 3839850415612.

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

It is a super-2 number, since 2×21651405893830² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

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, 1082570294682 + ... + 1082570294701.

It is an arithmetic number, because the mean of its divisors is an integer number (4871566326114).

Almost surely, 2^{21651405893830} is an apocalyptic number.

21651405893830 is a deficient number, since it is larger than the sum of its proper divisors (17321124715082).

21651405893830 is a wasteful number, since it uses less digits than its factorization.

21651405893830 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2165140589390.

The product of its (nonzero) digits is 6220800, while the sum is 55.

The spelling of 21651405893830 in words is "twenty-one trillion, six hundred fifty-one billion, four hundred five million, eight hundred ninety-three thousand, eight hundred thirty".