21958055 has 16 divisors (see below), whose sum is σ = 30411264. Its totient is φ = 14908320.

The previous prime is 21958049. The next prime is 21958061. The reversal of 21958055 is 55085912.

It is an interprime number because it is at equal distance from previous prime (21958049) and next prime (21958061).

It is not a de Polignac number, because 21958055 - 2⁴ = 21958039 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a Duffinian number.

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, 560 + ... + 6650.

It is an arithmetic number, because the mean of its divisors is an integer number (1900704).

Almost surely, 2^21958055 is an apocalyptic number.

21958055 is a deficient number, since it is larger than the sum of its proper divisors (8453209).

21958055 is a wasteful number, since it uses less digits than its factorization.

21958055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6206.

The product of its (nonzero) digits is 18000, while the sum is 35.

The square root of 21958055 is about 4685.9422745057. The cubic root of 21958055 is about 280.0257416810.

The spelling of 21958055 in words is "twenty-one million, nine hundred fifty-eight thousand, fifty-five".