13640534 has 4 divisors (see below), whose sum is σ = 20460804. Its totient is φ = 6820266.

The previous prime is 13640533. The next prime is 13640551. The reversal of 13640534 is 43504631.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 43504631 = 983 ⋅44257.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13640533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3410132 + ... + 3410135.

It is an arithmetic number, because the mean of its divisors is an integer number (5115201).

Almost surely, 2^13640534 is an apocalyptic number.

13640534 is a deficient number, since it is larger than the sum of its proper divisors (6820270).

13640534 is an equidigital number, since it uses as much as digits as its factorization.

13640534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6820269.

The product of its (nonzero) digits is 4320, while the sum is 26.

The square root of 13640534 is about 3693.3093561195. The cubic root of 13640534 is about 238.9335436103.

The spelling of 13640534 in words is "thirteen million, six hundred forty thousand, five hundred thirty-four".