21534651655641 has 12 divisors (see below), whose sum is σ = 31110990546480. Its totient is φ = 14353950160440.

The previous prime is 21534651655619. The next prime is 21534651655709. The reversal of 21534651655641 is 14655615643512.

21534651655641 is a `hidden beast` number, since 2 + 1 + 5 + 3 + 4 + 65 + 16 + 5 + 564 + 1 = 666.

It is not a de Polignac number, because 21534651655641 - 2⁷ = 21534651655513 is a prime.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (21534651655541) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 206968155 + ... + 207072176.

It is an arithmetic number, because the mean of its divisors is an integer number (2592582545540).

Almost surely, 2^{21534651655641} is an apocalyptic number.

It is an amenable number.

21534651655641 is a deficient number, since it is larger than the sum of its proper divisors (9576338890839).

21534651655641 is a wasteful number, since it uses less digits than its factorization.

21534651655641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414046116 (or 414046113 counting only the distinct ones).

The product of its digits is 12960000, while the sum is 54.

The spelling of 21534651655641 in words is "twenty-one trillion, five hundred thirty-four billion, six hundred fifty-one million, six hundred fifty-five thousand, six hundred forty-one".