61897680 has 240 divisors, whose sum is σ = 237641040. Its totient is φ = 14303232.

The previous prime is 61897639. The next prime is 61897699. The reversal of 61897680 is 8679816.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 4016016 + 57881664 = 2004^2 + 7608^2 .

It is a tau number, because it is divible by the number of its divisors (240).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 158926 + ... + 159314.

It is an arithmetic number, because the mean of its divisors is an integer number (990171).

Almost surely, 2^61897680 is an apocalyptic number.

61897680 is a gapful number since it is divisible by the number (60) 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 61897680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118820520).

61897680 is an abundant number, since it is smaller than the sum of its proper divisors (175743360).

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

61897680 is a wasteful number, since it uses less digits than its factorization.

61897680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438 (or 429 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The square root of 61897680 is about 7867.5078646291. The cubic root of 61897680 is about 395.5713144886.

The spelling of 61897680 in words is "sixty-one million, eight hundred ninety-seven thousand, six hundred eighty".