90653721 has 4 divisors (see below), whose sum is σ = 120871632. Its totient is φ = 60435812.

The previous prime is 90653713. The next prime is 90653729. The reversal of 90653721 is 12735609.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12735609 = 3 ⋅4245203.

It is an interprime number because it is at equal distance from previous prime (90653713) and next prime (90653729).

It is a cyclic number.

It is not a de Polignac number, because 90653721 - 2³ = 90653713 is a prime.

It is a super-3 number, since 3×90653721³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (90653729) 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, 15108951 + ... + 15108956.

It is an arithmetic number, because the mean of its divisors is an integer number (30217908).

Almost surely, 2^90653721 is an apocalyptic number.

It is an amenable number.

90653721 is a deficient number, since it is larger than the sum of its proper divisors (30217911).

90653721 is a wasteful number, since it uses less digits than its factorization.

90653721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30217910.

The product of its (nonzero) digits is 11340, while the sum is 33.

The square root of 90653721 is about 9521.2247636530. The cubic root of 90653721 is about 449.2228908744. Note that the first 3 decimals are identical.

The spelling of 90653721 in words is "ninety million, six hundred fifty-three thousand, seven hundred twenty-one".