2021398077 has 4 divisors (see below), whose sum is σ = 2695197440. Its totient is φ = 1347598716.

The previous prime is 2021398069. The next prime is 2021398157. The reversal of 2021398077 is 7708931202.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 2021398077 - 2³ = 2021398069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2021391077) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 336899677 + ... + 336899682.

It is an arithmetic number, because the mean of its divisors is an integer number (673799360).

Almost surely, 2^2021398077 is an apocalyptic number.

It is an amenable number.

2021398077 is a deficient number, since it is larger than the sum of its proper divisors (673799363).

2021398077 is an equidigital number, since it uses as much as digits as its factorization.

2021398077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 673799362.

The product of its (nonzero) digits is 42336, while the sum is 39.

The square root of 2021398077 is about 44959.9608207125. The cubic root of 2021398077 is about 1264.3984343615.

The spelling of 2021398077 in words is "two billion, twenty-one million, three hundred ninety-eight thousand, seventy-seven".