31720077 has 6 divisors (see below), whose sum is σ = 45817902. Its totient is φ = 21146712.

The previous prime is 31720049. The next prime is 31720103. The reversal of 31720077 is 77002713.

It can be written as a sum of positive squares in only one way, i.e., 21261321 + 10458756 = 4611^2 + 3234^2 .

It is not a de Polignac number, because 31720077 - 2¹⁵ = 31687309 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31720077.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31720277) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1762218 + ... + 1762235.

It is an arithmetic number, because the mean of its divisors is an integer number (7636317).

Almost surely, 2^31720077 is an apocalyptic number.

It is an amenable number.

31720077 is a deficient number, since it is larger than the sum of its proper divisors (14097825).

31720077 is a wasteful number, since it uses less digits than its factorization.

31720077 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3524459 (or 3524456 counting only the distinct ones).

The product of its (nonzero) digits is 2058, while the sum is 27.

The square root of 31720077 is about 5632.0579720028. The cubic root of 31720077 is about 316.5517685960.

The spelling of 31720077 in words is "thirty-one million, seven hundred twenty thousand, seventy-seven".