51532639 has 4 divisors (see below), whose sum is σ = 51794424. Its totient is φ = 51270856.

The previous prime is 51532609. The next prime is 51532643. The reversal of 51532639 is 93623515.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93623515 = 5 ⋅18724703.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51532639 is a prime.

It is a super-2 number, since 2×51532639² = 5311225764608642, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51532609) 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, 130597 + ... + 130990.

It is an arithmetic number, because the mean of its divisors is an integer number (12948606).

Almost surely, 2^51532639 is an apocalyptic number.

51532639 is a deficient number, since it is larger than the sum of its proper divisors (261785).

51532639 is a wasteful number, since it uses less digits than its factorization.

51532639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 261784.

The product of its digits is 24300, while the sum is 34.

The square root of 51532639 is about 7178.6237538960. The cubic root of 51532639 is about 372.1295243072.

It can be divided in two parts, 5 and 1532639, that added together give a square (1532644 = 1238²).

The spelling of 51532639 in words is "fifty-one million, five hundred thirty-two thousand, six hundred thirty-nine".