642511253 has 8 divisors (see below), whose sum is σ = 661158048. Its totient is φ = 623931984.

The previous prime is 642511249. The next prime is 642511271. The reversal of 642511253 is 352115246.

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

It is a cyclic number.

It is not a de Polignac number, because 642511253 - 2² = 642511249 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 (642511273) 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, 2750 + ... + 35952.

It is an arithmetic number, because the mean of its divisors is an integer number (82644756).

Almost surely, 2^642511253 is an apocalyptic number.

It is an amenable number.

642511253 is a deficient number, since it is larger than the sum of its proper divisors (18646795).

642511253 is a wasteful number, since it uses less digits than its factorization.

642511253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33763.

The product of its digits is 7200, while the sum is 29.

The square root of 642511253 is about 25347.8056841219. The cubic root of 642511253 is about 862.8995571697.

Adding to 642511253 its reverse (352115246), we get a palindrome (994626499).

The spelling of 642511253 in words is "six hundred forty-two million, five hundred eleven thousand, two hundred fifty-three".