634986540 has 60 divisors (see below), whose sum is σ = 1991981376. Its totient is φ = 169329312.

The previous prime is 634986529. The next prime is 634986551. The reversal of 634986540 is 45689436.

634986540 is a `hidden beast` number, since 63 + 49 + 8 + 6 + 540 = 666.

It is an interprime number because it is at equal distance from previous prime (634986529) and next prime (634986551).

It is a tau number, because it is divible by the number of its divisors (60).

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 194364 + ... + 197603.

Almost surely, 2^634986540 is an apocalyptic number.

634986540 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

634986540 is an abundant number, since it is smaller than the sum of its proper divisors (1356994836).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

634986540 is a wasteful number, since it uses less digits than its factorization.

634986540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 391988 (or 391977 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 45.

The square root of 634986540 is about 25198.9392633896. The cubic root of 634986540 is about 859.5177303251.

The spelling of 634986540 in words is "six hundred thirty-four million, nine hundred eighty-six thousand, five hundred forty".