61444864 has 72 divisors (see below), whose sum is σ = 135926000. Its totient is φ = 27537408.

The previous prime is 61444853. The next prime is 61444871. The reversal of 61444864 is 46844416.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 122887 + ... + 123385.

Almost surely, 2^61444864 is an apocalyptic number.

61444864 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61444864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67963000).

61444864 is an abundant number, since it is smaller than the sum of its proper divisors (74481136).

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

61444864 is a wasteful number, since it uses less digits than its factorization.

61444864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 565 (or 551 counting only the distinct ones).

The product of its digits is 73728, while the sum is 37.

The square root of 61444864 is about 7838.6774394664. The cubic root of 61444864 is about 394.6043445135.

The spelling of 61444864 in words is "sixty-one million, four hundred forty-four thousand, eight hundred sixty-four".