21154735 has 16 divisors (see below), whose sum is σ = 29094912. Its totient is φ = 14464800.

The previous prime is 21154711. The next prime is 21154759. The reversal of 21154735 is 53745112.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21154711) and next prime (21154759).

It is not a de Polignac number, because 21154735 - 2¹⁵ = 21121967 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16570 + ... + 17800.

It is an arithmetic number, because the mean of its divisors is an integer number (1818432).

Almost surely, 2^21154735 is an apocalyptic number.

21154735 is a deficient number, since it is larger than the sum of its proper divisors (7940177).

21154735 is a wasteful number, since it uses less digits than its factorization.

21154735 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1734.

The product of its digits is 4200, while the sum is 28.

The square root of 21154735 is about 4599.4276817882. The cubic root of 21154735 is about 276.5683825342.

Adding to 21154735 its reverse (53745112), we get a palindrome (74899847).

It can be divided in two parts, 211 and 54735, that added together give a triangular number (54946 = T₃₃₁).

The spelling of 21154735 in words is "twenty-one million, one hundred fifty-four thousand, seven hundred thirty-five".