20770345021 has 4 divisors (see below), whose sum is σ = 21276938844. Its totient is φ = 20263751200.

The previous prime is 20770345003. The next prime is 20770345027. The reversal of 20770345021 is 12054307702.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1619660025 + 19150684996 = 40245^2 + 138386^2 .

It is a cyclic number.

It is not a de Polignac number, because 20770345021 - 2⁵ = 20770344989 is a prime.

It is a super-4 number, since 4×20770345021⁴ (a number of 42 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20770345027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 253296850 + ... + 253296931.

It is an arithmetic number, because the mean of its divisors is an integer number (5319234711).

Almost surely, 2^20770345021 is an apocalyptic number.

It is an amenable number.

20770345021 is a deficient number, since it is larger than the sum of its proper divisors (506593823).

20770345021 is an equidigital number, since it uses as much as digits as its factorization.

20770345021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 506593822.

The product of its (nonzero) digits is 11760, while the sum is 31.

The spelling of 20770345021 in words is "twenty billion, seven hundred seventy million, three hundred forty-five thousand, twenty-one".