51451639 has 8 divisors (see below), whose sum is σ = 57345840. Its totient is φ = 45876096.

The previous prime is 51451627. The next prime is 51451663. The reversal of 51451639 is 93615415.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51451639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51451619) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79324 + ... + 79969.

It is an arithmetic number, because the mean of its divisors is an integer number (7168230).

Almost surely, 2^51451639 is an apocalyptic number.

51451639 is a deficient number, since it is larger than the sum of its proper divisors (5894201).

51451639 is a wasteful number, since it uses less digits than its factorization.

51451639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159329.

The product of its digits is 16200, while the sum is 34.

The square root of 51451639 is about 7172.9797852775. The cubic root of 51451639 is about 371.9344485992.

The spelling of 51451639 in words is "fifty-one million, four hundred fifty-one thousand, six hundred thirty-nine".