61651920 has 160 divisors (see below), whose sum is σ = 211307904. Its totient is φ = 14868480.

The previous prime is 61651913. The next prime is 61651951. The reversal of 61651920 is 2915616.

It is a Harshad number since it is a multiple of its sum of digits (30).

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, 319344 + ... + 319536.

Almost surely, 2^61651920 is an apocalyptic number.

61651920 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 61651920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105653952).

61651920 is an abundant number, since it is smaller than the sum of its proper divisors (149655984).

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

61651920 is a wasteful number, since it uses less digits than its factorization.

61651920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242 (or 214 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 30.

The square root of 61651920 is about 7851.8736617447. The cubic root of 61651920 is about 395.0470915388.

The spelling of 61651920 in words is "sixty-one million, six hundred fifty-one thousand, nine hundred twenty".