61997520 has 160 divisors (see below), whose sum is σ = 213986304. Its totient is φ = 14745600.

The previous prime is 61997503. The next prime is 61997531. The reversal of 61997520 is 2579916.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 96400 + ... + 97040.

Almost surely, 2^61997520 is an apocalyptic number.

61997520 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 61997520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106993152).

61997520 is an abundant number, since it is smaller than the sum of its proper divisors (151988784).

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

61997520 is a wasteful number, since it uses less digits than its factorization.

61997520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 701 (or 695 counting only the distinct ones).

The product of its (nonzero) digits is 34020, while the sum is 39.

The square root of 61997520 is about 7873.8503922795. The cubic root of 61997520 is about 395.7838837089.

The spelling of 61997520 in words is "sixty-one million, nine hundred ninety-seven thousand, five hundred twenty".