87720922 has 8 divisors (see below), whose sum is σ = 131718996. Its totient is φ = 43814592.

The previous prime is 87720869. The next prime is 87720923. The reversal of 87720922 is 22902778.

It can be written as a sum of positive squares in 2 ways, for example, as 81018001 + 6702921 = 9001^2 + 2589^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (87720923) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20493 + ... + 24400.

Almost surely, 2^87720922 is an apocalyptic number.

87720922 is a deficient number, since it is larger than the sum of its proper divisors (43998074).

87720922 is a wasteful number, since it uses less digits than its factorization.

87720922 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45872.

The product of its (nonzero) digits is 28224, while the sum is 37.

The square root of 87720922 is about 9365.9448001790. The cubic root of 87720922 is about 444.3253202454.

The spelling of 87720922 in words is "eighty-seven million, seven hundred twenty thousand, nine hundred twenty-two".