634542221 has 16 divisors (see below), whose sum is σ = 715780800. Its totient is φ = 558943488.

The previous prime is 634542179. The next prime is 634542241. The reversal of 634542221 is 122245436.

It is a cyclic number.

It is not a de Polignac number, because 634542221 - 2²⁶ = 567433357 is a prime.

It is a super-2 number, since 2×634542221² = 805287660463225682, 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 (634542241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14975 + ... + 38643.

It is an arithmetic number, because the mean of its divisors is an integer number (44736300).

Almost surely, 2^634542221 is an apocalyptic number.

It is an amenable number.

634542221 is a deficient number, since it is larger than the sum of its proper divisors (81238579).

634542221 is a wasteful number, since it uses less digits than its factorization.

634542221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23788.

The product of its digits is 11520, while the sum is 29.

The square root of 634542221 is about 25190.1214963326. The cubic root of 634542221 is about 859.3172068260.

Adding to 634542221 its reverse (122245436), we get a palindrome (756787657).

The spelling of 634542221 in words is "six hundred thirty-four million, five hundred forty-two thousand, two hundred twenty-one".