21405377350412 has 96 divisors (see below), whose sum is σ = 41924541689856. Its totient is φ = 9480727872000.

The previous prime is 21405377350381. The next prime is 21405377350507.

It is a happy number.

21405377350412 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 323619008 + ... + 323685144.

It is an arithmetic number, because the mean of its divisors is an integer number (436713975936).

Almost surely, 2^{21405377350412} is an apocalyptic number.

21405377350412 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21405377350412 is a deficient number, since it is larger than the sum of its proper divisors (20519164339444).

21405377350412 is a wasteful number, since it uses less digits than its factorization.

21405377350412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67407 (or 67405 counting only the distinct ones).

The product of its (nonzero) digits is 705600, while the sum is 44.

It can be divided in two parts, 2140537 and 7350412, that added together give a palindrome (9490949).

The spelling of 21405377350412 in words is "twenty-one trillion, four hundred five billion, three hundred seventy-seven million, three hundred fifty thousand, four hundred twelve".