20605212351 has 16 divisors (see below), whose sum is σ = 30577741920. Its totient is φ = 13713632640.

The previous prime is 20605212343. The next prime is 20605212371. The reversal of 20605212351 is 15321250602.

It is a happy number.

20605212351 is a `hidden beast` number, since 2 + 0 + 605 + 2 + 1 + 2 + 3 + 51 = 666.

It is not a de Polignac number, because 20605212351 - 2³ = 20605212343 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20605212301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 627460 + ... + 659481.

It is an arithmetic number, because the mean of its divisors is an integer number (1911108870).

Almost surely, 2^20605212351 is an apocalyptic number.

20605212351 is a deficient number, since it is larger than the sum of its proper divisors (9972529569).

20605212351 is a wasteful number, since it uses less digits than its factorization.

20605212351 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1287543 (or 1287537 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

Adding to 20605212351 its reverse (15321250602), we get a palindrome (35926462953).

The spelling of 20605212351 in words is "twenty billion, six hundred five million, two hundred twelve thousand, three hundred fifty-one".