90720551 has 8 divisors (see below), whose sum is σ = 96169680. Its totient is φ = 85283968.

The previous prime is 90720529. The next prime is 90720571. The reversal of 90720551 is 15502709.

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

It is not a de Polignac number, because 90720551 - 2¹⁴ = 90704167 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90720521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14705 + ... + 19941.

It is an arithmetic number, because the mean of its divisors is an integer number (12021210).

Almost surely, 2^90720551 is an apocalyptic number.

90720551 is a deficient number, since it is larger than the sum of its proper divisors (5449129).

90720551 is a wasteful number, since it uses less digits than its factorization.

90720551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6273.

The product of its (nonzero) digits is 3150, while the sum is 29.

The square root of 90720551 is about 9524.7336445698. The cubic root of 90720551 is about 449.3332529245. Note that the first 3 decimals are identical.

The spelling of 90720551 in words is "ninety million, seven hundred twenty thousand, five hundred fifty-one".