90642451 has 4 divisors (see below), whose sum is σ = 90965304. Its totient is φ = 90319600.

The previous prime is 90642449. The next prime is 90642457. The reversal of 90642451 is 15424609.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15424609 = 179 ⋅86171.

It is a cyclic number.

It is not a de Polignac number, because 90642451 - 2¹ = 90642449 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90642457) 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, 161005 + ... + 161566.

It is an arithmetic number, because the mean of its divisors is an integer number (22741326).

Almost surely, 2^90642451 is an apocalyptic number.

90642451 is a deficient number, since it is larger than the sum of its proper divisors (322853).

90642451 is a wasteful number, since it uses less digits than its factorization.

90642451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322852.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 90642451 is about 9520.6329096337. The cubic root of 90642451 is about 449.2042744229.

The spelling of 90642451 in words is "ninety million, six hundred forty-two thousand, four hundred fifty-one".