42640894 has 4 divisors (see below), whose sum is σ = 63961344. Its totient is φ = 21320446.

The previous prime is 42640859. The next prime is 42640901. The reversal of 42640894 is 49804624.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×42640894² = 3636491682238472, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10660222 + ... + 10660225.

It is an arithmetic number, because the mean of its divisors is an integer number (15990336).

Almost surely, 2^42640894 is an apocalyptic number.

42640894 is a deficient number, since it is larger than the sum of its proper divisors (21320450).

42640894 is a wasteful number, since it uses less digits than its factorization.

42640894 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21320449.

The product of its (nonzero) digits is 55296, while the sum is 37.

The square root of 42640894 is about 6529.9995405819. Note that the first 3 decimals coincide. The cubic root of 42640894 is about 349.3618139167.

It can be divided in two parts, 42640 and 894, that added together give a palindrome (43534).

The spelling of 42640894 in words is "forty-two million, six hundred forty thousand, eight hundred ninety-four".