20634530661 has 24 divisors (see below), whose sum is σ = 31124598336. Its totient is φ = 13148403840.

The previous prime is 20634530641. The next prime is 20634530681. The reversal of 20634530661 is 16603543602.

20634530661 is a `hidden beast` number, since 2 + 0 + 6 + 345 + 306 + 6 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (20634530641) and next prime (20634530681).

It is not a de Polignac number, because 20634530661 - 2¹⁹ = 20634006373 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20634530641) 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, 245106 + ... + 318348.

It is an arithmetic number, because the mean of its divisors is an integer number (1296858264).

Almost surely, 2^20634530661 is an apocalyptic number.

It is an amenable number.

20634530661 is a deficient number, since it is larger than the sum of its proper divisors (10490067675).

20634530661 is a wasteful number, since it uses less digits than its factorization.

20634530661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74633 (or 74630 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 36.

The spelling of 20634530661 in words is "twenty billion, six hundred thirty-four million, five hundred thirty thousand, six hundred sixty-one".