21671956035 has 24 divisors (see below), whose sum is σ = 39541816080. Its totient is φ = 10950040512.

The previous prime is 21671955971. The next prime is 21671956037. The reversal of 21671956035 is 53065917612.

21671956035 is a `hidden beast` number, since 2 + 16 + 71 + 9 + 560 + 3 + 5 = 666.

It is not a de Polignac number, because 21671956035 - 2⁶ = 21671955971 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (21671956037) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12672804 + ... + 12674513.

It is an arithmetic number, because the mean of its divisors is an integer number (1647575670).

Almost surely, 2^21671956035 is an apocalyptic number.

21671956035 is a deficient number, since it is larger than the sum of its proper divisors (17869860045).

21671956035 is a wasteful number, since it uses less digits than its factorization.

21671956035 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25347347 (or 25347344 counting only the distinct ones).

The product of its (nonzero) digits is 340200, while the sum is 45.

The spelling of 21671956035 in words is "twenty-one billion, six hundred seventy-one million, nine hundred fifty-six thousand, thirty-five".