20546068921 has 9 divisors (see below), whose sum is σ = 23901696399. Its totient is φ = 17610056184.

The previous prime is 20546068919. The next prime is 20546068943. The reversal of 20546068921 is 12986064502.

The square root of 20546068921 is 143339.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 16168394025 + 4377674896 = 127155^2 + 66164^2 .

It is not a de Polignac number, because 20546068921 - 2¹ = 20546068919 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20546018921) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 993135 + ... + 1013611.

Almost surely, 2^20546068921 is an apocalyptic number.

20546068921 is the 143339-th square number.

20546068921 is the 71670-th centered octagonal number.

It is an amenable number.

20546068921 is a deficient number, since it is larger than the sum of its proper divisors (3355627478).

20546068921 is an frugal number, since it uses more digits than its factorization.

20546068921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40968 (or 20484 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 43.

The spelling of 20546068921 in words is "twenty billion, five hundred forty-six million, sixty-eight thousand, nine hundred twenty-one".