31438409 has 4 divisors (see below), whose sum is σ = 31603200. Its totient is φ = 31273620.

The previous prime is 31438403. The next prime is 31438411. The reversal of 31438409 is 90483413.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 90483413 = 47 ⋅1925179.

It is a cyclic number.

It is not a de Polignac number, because 31438409 - 2⁸ = 31438153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31438403) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82109 + ... + 82490.

It is an arithmetic number, because the mean of its divisors is an integer number (7900800).

Almost surely, 2^31438409 is an apocalyptic number.

It is an amenable number.

31438409 is a deficient number, since it is larger than the sum of its proper divisors (164791).

31438409 is a wasteful number, since it uses less digits than its factorization.

31438409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164790.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 31438409 is about 5606.9964330290. The cubic root of 31438409 is about 315.6120091245.

The spelling of 31438409 in words is "thirty-one million, four hundred thirty-eight thousand, four hundred nine".