62640021 has 4 divisors (see below), whose sum is σ = 83520032. Its totient is φ = 41760012.

The previous prime is 62639989. The next prime is 62640023. The reversal of 62640021 is 12004626.

It is a happy number.

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.

It is not a de Polignac number, because 62640021 - 2⁵ = 62639989 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 62640021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (62640023) 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, 10440001 + ... + 10440006.

It is an arithmetic number, because the mean of its divisors is an integer number (20880008).

Almost surely, 2^62640021 is an apocalyptic number.

It is an amenable number.

62640021 is a deficient number, since it is larger than the sum of its proper divisors (20880011).

62640021 is a wasteful number, since it uses less digits than its factorization.

62640021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20880010.

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 62640021 is about 7914.5449016352. The cubic root of 62640021 is about 397.1464012625.

Adding to 62640021 its reverse (12004626), we get a palindrome (74644647).

The spelling of 62640021 in words is "sixty-two million, six hundred forty thousand, twenty-one".