31690143 has 8 divisors (see below), whose sum is σ = 46948400. Its totient is φ = 21126744.

The previous prime is 31690133. The next prime is 31690151. The reversal of 31690143 is 34109613.

It is not a de Polignac number, because 31690143 - 2⁵ = 31690111 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 1173709 = 31690143 / (3 + 1 + 6 + 9 + 0 + 1 + 4 + 3).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31690123) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 586828 + ... + 586881.

It is an arithmetic number, because the mean of its divisors is an integer number (5868550).

Almost surely, 2^31690143 is an apocalyptic number.

31690143 is a deficient number, since it is larger than the sum of its proper divisors (15258257).

31690143 is a wasteful number, since it uses less digits than its factorization.

31690143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1173718 (or 1173712 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 27.

The square root of 31690143 is about 5629.3998792056. The cubic root of 31690143 is about 316.4521614091.

Adding to 31690143 its reverse (34109613), we get a palindrome (65799756).

The spelling of 31690143 in words is "thirty-one million, six hundred ninety thousand, one hundred forty-three".