21404612312061 has 16 divisors (see below), whose sum is σ = 31134765892608. Its totient is φ = 12972165498800.

The previous prime is 21404612312047. The next prime is 21404612312077. The reversal of 21404612312061 is 16021321640412.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21404612312061 - 2⁵ = 21404612312029 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21404612312081) 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, 6837291 + ... + 9463496.

It is an arithmetic number, because the mean of its divisors is an integer number (1945922868288).

Almost surely, 2^{21404612312061} is an apocalyptic number.

It is an amenable number.

21404612312061 is a deficient number, since it is larger than the sum of its proper divisors (9730153580547).

21404612312061 is a wasteful number, since it uses less digits than its factorization.

21404612312061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16340592.

The product of its (nonzero) digits is 13824, while the sum is 33.

Adding to 21404612312061 its reverse (16021321640412), we get a palindrome (37425933952473).

The spelling of 21404612312061 in words is "twenty-one trillion, four hundred four billion, six hundred twelve million, three hundred twelve thousand, sixty-one".