84402765621 has 6 divisors (see below), whose sum is σ = 121915105910. Its totient is φ = 56268510408.

The previous prime is 84402765619. The next prime is 84402765631. The reversal of 84402765621 is 12656720448.

84402765621 is a `hidden beast` number, since 84 + 4 + 0 + 2 + 7 + 6 + 562 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 70710255396 + 13692510225 = 265914^2 + 117015^2 .

It is not a de Polignac number, because 84402765621 - 2¹ = 84402765619 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84402765611) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4689042526 + ... + 4689042543.

Almost surely, 2^84402765621 is an apocalyptic number.

It is an amenable number.

84402765621 is a deficient number, since it is larger than the sum of its proper divisors (37512340289).

84402765621 is a wasteful number, since it uses less digits than its factorization.

84402765621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9378085075 (or 9378085072 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 45.

The spelling of 84402765621 in words is "eighty-four billion, four hundred two million, seven hundred sixty-five thousand, six hundred twenty-one".