20498721 has 8 divisors (see below), whose sum is σ = 27913344. Its totient is φ = 13374960.

The previous prime is 20498707. The next prime is 20498741. The reversal of 20498721 is 12789402.

It is a happy number.

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

It is not a de Polignac number, because 20498721 - 2¹⁴ = 20482337 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20498741) 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, 72550 + ... + 72831.

It is an arithmetic number, because the mean of its divisors is an integer number (3489168).

Almost surely, 2^20498721 is an apocalyptic number.

It is an amenable number.

20498721 is a deficient number, since it is larger than the sum of its proper divisors (7414623).

20498721 is a wasteful number, since it uses less digits than its factorization.

20498721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145431.

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 20498721 is about 4527.5513249438. The cubic root of 20498721 is about 273.6794918598.

The spelling of 20498721 in words is "twenty million, four hundred ninety-eight thousand, seven hundred twenty-one".