31220045 has 12 divisors (see below), whose sum is σ = 38512404. Its totient is φ = 24295680.

The previous prime is 31220023. The next prime is 31220053. The reversal of 31220045 is 54002213.

31220045 = T₄₈₆ + T₄₈₇ + ... + T₆₇₀.

It can be written as a sum of positive squares in 6 ways, for example, as 2725801 + 28494244 = 1651^2 + 5338^2 .

It is not a de Polignac number, because 31220045 - 2²² = 27025741 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4565 + ... + 9125.

It is an arithmetic number, because the mean of its divisors is an integer number (3209367).

Almost surely, 2^31220045 is an apocalyptic number.

It is an amenable number.

31220045 is a deficient number, since it is larger than the sum of its proper divisors (7292359).

31220045 is an equidigital number, since it uses as much as digits as its factorization.

31220045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4640 (or 4603 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 31220045 is about 5587.4900447339. The cubic root of 31220045 is about 314.8795878058.

Adding to 31220045 its reverse (54002213), we get a palindrome (85222258).

The spelling of 31220045 in words is "thirty-one million, two hundred twenty thousand, forty-five".