78161520 has 40 divisors (see below), whose sum is σ = 242301456. Its totient is φ = 20843008.

The previous prime is 78161519. The next prime is 78161527. The reversal of 78161520 is 2516187.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×78161520² = 12218446417420800, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78161527) by changing a digit.

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, 162597 + ... + 163076.

Almost surely, 2^78161520 is an apocalyptic number.

It is an amenable number.

78161520 is an abundant number, since it is smaller than the sum of its proper divisors (164139936).

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

78161520 is a wasteful number, since it uses less digits than its factorization.

78161520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 325689 (or 325683 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 30.

The square root of 78161520 is about 8840.9004066328. The cubic root of 78161520 is about 427.5605878356.

The spelling of 78161520 in words is "seventy-eight million, one hundred sixty-one thousand, five hundred twenty".