31436021 has 2 divisors, whose sum is σ = 31436022. Its totient is φ = 31436020.

The previous prime is 31435979. The next prime is 31436039. The reversal of 31436021 is 12063413.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30195025 + 1240996 = 5495^2 + 1114^2 .

It is a cyclic number.

It is not a de Polignac number, because 31436021 - 2¹⁴ = 31419637 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 31435984 and 31436002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31436521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15718010 + 15718011.

It is an arithmetic number, because the mean of its divisors is an integer number (15718011).

Almost surely, 2^31436021 is an apocalyptic number.

It is an amenable number.

31436021 is a deficient number, since it is larger than the sum of its proper divisors (1).

31436021 is an equidigital number, since it uses as much as digits as its factorization.

31436021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 31436021 is about 5606.7834807490. The cubic root of 31436021 is about 315.6040178320.

Adding to 31436021 its reverse (12063413), we get a palindrome (43499434).

The spelling of 31436021 in words is "thirty-one million, four hundred thirty-six thousand, twenty-one".