21901434 has 16 divisors (see below), whose sum is σ = 44191872. Its totient is φ = 7235648.

The previous prime is 21901427. The next prime is 21901463. The reversal of 21901434 is 43410912.

It is a super-2 number, since 2×21901434² = 959345622512712, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15474 + ... + 16829.

It is an arithmetic number, because the mean of its divisors is an integer number (2761992).

Almost surely, 2^21901434 is an apocalyptic number.

21901434 is an abundant number, since it is smaller than the sum of its proper divisors (22290438).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21901434 is a wasteful number, since it uses less digits than its factorization.

21901434 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32421.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 21901434 is about 4679.8967937338. The cubic root of 21901434 is about 279.7848432156.

The spelling of 21901434 in words is "twenty-one million, nine hundred one thousand, four hundred thirty-four".