21498077 has 16 divisors (see below), whose sum is σ = 23466240. Its totient is φ = 19633152.

The previous prime is 21498067. The next prime is 21498083. The reversal of 21498077 is 77089412.

It is a cyclic number.

It is not a de Polignac number, because 21498077 - 2¹⁰ = 21497053 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 21498077.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21498067) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 111293 + ... + 111485.

It is an arithmetic number, because the mean of its divisors is an integer number (1466640).

Almost surely, 2^21498077 is an apocalyptic number.

It is an amenable number.

21498077 is a deficient number, since it is larger than the sum of its proper divisors (1968163).

21498077 is a wasteful number, since it uses less digits than its factorization.

21498077 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 412.

The product of its (nonzero) digits is 28224, while the sum is 38.

The square root of 21498077 is about 4636.6018806881. The cubic root of 21498077 is about 278.0565978652.

The spelling of 21498077 in words is "twenty-one million, four hundred ninety-eight thousand, seventy-seven".