61631520 has 48 divisors (see below), whose sum is σ = 194140800. Its totient is φ = 16434944.

The previous prime is 61631519. The next prime is 61631539. The reversal of 61631520 is 2513616.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63720 + ... + 64679.

It is an arithmetic number, because the mean of its divisors is an integer number (4044600).

Almost surely, 2^61631520 is an apocalyptic number.

61631520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61631520 is an abundant number, since it is smaller than the sum of its proper divisors (132509280).

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

61631520 is a wasteful number, since it uses less digits than its factorization.

61631520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128417 (or 128409 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 61631520 is about 7850.5745012706. The cubic root of 61631520 is about 395.0035143628.

The spelling of 61631520 in words is "sixty-one million, six hundred thirty-one thousand, five hundred twenty".