39870021077 has 4 divisors (see below), whose sum is σ = 41244849420. Its totient is φ = 38495192736.

The previous prime is 39870021053. The next prime is 39870021089. The reversal of 39870021077 is 77012007893.

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 13835875876 + 26034145201 = 117626^2 + 161351^2 .

It is a cyclic number.

It is not a de Polignac number, because 39870021077 - 2²⁶ = 39802912213 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 (39870021007) 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, 687414128 + ... + 687414185.

It is an arithmetic number, because the mean of its divisors is an integer number (10311212355).

Almost surely, 2^39870021077 is an apocalyptic number.

It is an amenable number.

39870021077 is a deficient number, since it is larger than the sum of its proper divisors (1374828343).

39870021077 is a wasteful number, since it uses less digits than its factorization.

39870021077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1374828342.

The product of its (nonzero) digits is 148176, while the sum is 44.

The spelling of 39870021077 in words is "thirty-nine billion, eight hundred seventy million, twenty-one thousand, seventy-seven".