21406373477 has 8 divisors (see below), whose sum is σ = 22008016800. Its totient is φ = 20809449360.

The previous prime is 21406373473. The next prime is 21406373491. The reversal of 21406373477 is 77437360412.

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

It is a cyclic number.

It is not a de Polignac number, because 21406373477 - 2² = 21406373473 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21406373473) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1170602 + ... + 1188747.

It is an arithmetic number, because the mean of its divisors is an integer number (2751002100).

Almost surely, 2^21406373477 is an apocalyptic number.

It is an amenable number.

21406373477 is a deficient number, since it is larger than the sum of its proper divisors (601643323).

21406373477 is a wasteful number, since it uses less digits than its factorization.

21406373477 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2359603.

The product of its (nonzero) digits is 592704, while the sum is 44.

The spelling of 21406373477 in words is "twenty-one billion, four hundred six million, three hundred seventy-three thousand, four hundred seventy-seven".